What is its velocity when it reaches its maximum altitude. From these observations, we use Equation \ref{3.
What is its velocity when it reaches its maximum altitude. The acceleration of an object falling freely, just before it hits the ground equals acceleration due to gravity. The acceleration of the ball is 9. 81 m / s 2 h ' h ' = 252. Why?, If a car is traveling eastward, can its Question: You throw a ball vertically upward so that it leaves the ground with velocity 4. Does its acceleration increase, decrease, or Jan 28, 2018 · The velocity of the ball when it reaches its maximum altitude is Explanation: This is a vertical shot , and we know that in this kind of motion, the particle (in this case the ball) starts with a given velocity , in this problem given by What are its velocity and acceleration when it reaches its maximum altitude? You throw a ball vertically upward so that it leaves the ground with velocity +5. 56 m/s. (a) What is its velocity when it reaches its maximum altitude? magnitude direction ---Select- m/s (b) What is its acceleration at this point? magnitude m/s2 direction Select-- V (c) What is the velocity with which it returns to ground level? magnitude m/s direction Study with Quizlet and memorize flashcards containing terms like You toss a ball to your friend. It accelerates upward at 4 m/s2 until it reaches an altitude of 1000 m when its engines fail and it is influenced only by the Earth's gravity. 8 m Question: You throw a ball vertically upward so that it leaves the ground with velocity 2. 00 m/s^{2}$$ until it reaches an altitude of $$1 000 m$$. A catapult launches a test rocket vertically upward from a well, giving the rocket an initial speed of 80. (a) What is its velocity when it reaches its maximum altitude? (b) What is its acceleration at this point? (c) What is the velocity with which it returns to ground level? (d) What is its accel eration at this point? A catapult launches a test rocket vertically upward from a well, giving the rocket an initial speed of $$80. The velocity with which it returns to ground level is -5. 63 m/s and the acceleration at this point is also -9. May 25, 2024 · At the very top of the ball's path, its velocity is momentarily zero. (a) What is its velocity when it reaches its maximum altitude? Your solution’s ready to go! Enhanced with AI, our expert help has broken down your problem into an easy-to-learn solution you can count on. Its acceleration is -9. Sep 22, 2022 · What are its initial, its velocity and acceleration when it reaches its maximum altitudes a ball. Find (a) the maximum altitude reached by the rocket, (b) its total time of flight, and (c) its horizontal range. So the lowest position here velocity is decreasing and here we lost is increasing at the maximum height velocity zero. At this point, its velocity is zero. At the maximum altitude, the velocity of the ball is 0 m/s. Therefore, the initial velocity of the object is 14 m/s. Does its acceleration increase, decrease, or remain constant? Feb 3, 2010 · A test rocket is fired vertically upward from a well. what happens to the ball's velocity while the ball is in the air? b. 6 shows strobe photographs taken of a disk mov- ing from left to right under different conditions. Question: You throw a ball vertically upward so that it leaves the ground with velocity 5. and more. On plugging the values in the above relation, 0 = 70. At that point, its engines fail and the rocket goes into free fall, with an acceleration of −9. Answer 4. Question: You throw a ball vertically upward so that it leaves the ground with velocity + 5. Question: You throw a ball vertically upward so that it leaves the ground with velocity 4. 8m (a) What is its velocity when it reaches its maximum altitude? magnitude m/s direction ---Select--- up no direction down (b) What is its acceleration at this point? You throw a ball vertically upward so that it leaves the ground with velocity 4. The initial velocity is you. At the maximum altitude, the ball's acceleration is equal to the acceleration due to gravity, which is approximately 9. The acceleration at this point is -9. As the ball moves upward, its velocity decreases until it reaches its maximum altitude. (a) What is its velocity when it reaches its maximum altitude? (b) What is its acceleration at this point? (c) What is the velocity with which it returns to ground level? (d) What is its acceleration at this point? Oct 2, 2024 · Study with Quizlet and memorize flashcards containing terms like if the average velocity of a duck is zero in a given time interval, what can you say about the displacement of the duck for that interval, Velocity can be either positive or negative, depending on the direction of the displacement. 49 m/s (a) What is its velocity when it reaches its maximum altitude? magnitude m/s direction (b) What is its acceleration at this point? magnitude m/s2 direction (c) What is the velocity with which it returns to ground level? magnitude A ball is thrown vertically upward. Assuming that v 2 /g is constant, the greatest distance will be when sin(2θ) is at its maximum, which is when 2θ = 90 degrees. What distance does the ball travel horizontally? Science; Physics; Physics questions and answers; Problem 1 A rocket is fired vertically upward with an initial velocity of 80 m/s. 0 m/s at ground level. Therefore, the time taken by the object to reach the highest point is 1. Thus, H = 1027 Jan 9, 2023 · You throw a ball vertically upward so that it leaves the ground with velocity 5. Since we know the initial velocity, initial position, and the value of v y when the firework reaches its maximum height, we use the following equation Maximum altitude is the highest point an object reaches during its motion. (b) At the maximum altitude, the ball's velocity is 0 m/s, and since acceleration is the change in velocity per unit time, the acceleration will also be 0 m / s 2 0 m/s^2 0 m / s 2 because there is no change in velocity at this point. 80 m/s². 00 m/s2 until it reaches an altitude of 1 000 m. You throw a ball vertically upward so that it leaves the ground with velocity 1 5. 6 m H = 1027. 43 seconds. 0 m/s^{2}$$. What happens to the ballâs velocity while the ball is in the air? b. Does its acceleration increase, decrease, or Science; Physics; Physics questions and answers; You throw a ball vertically upward so that it leaves the ground with velocity 2. eration at this point? (c) What is the velocity with which it returns to ground level? (d) What is its acceleration at this point? Jul 26, 2024 · For a given velocity V, this function reaches its maximum value when sin (α) = 1, which occurs at α = 90°. During the upwards bit the acceleration of gravity g=9. Since the initial velocity of the object is pointing vertically up, and its final velocity is pointing vertically down, it can be concluded that the object is experiencing a vertical acceleration that is pointing downwards. Just before hitting the ground, the acceleration of the a. Does its acceleration decrease, increase or remain constant? You throw a ball vertically upward so that it leaves the ground with velocity 5. From these observations, we use Equation \ref{3. What is its acceleration just before it hits the ground? e. 76 m/s. M/s direction Incorrect: Your answer is incorrect. H = h + h ' H = 775 m + 252. what is its acceleration when it reaches its maximum altitude? d. (a) What are its velocity and acceleration when it reaches its maximum altitude? (b) What is the acceleration of the ball just before it hits the ground? a 9. 24 m/s. What are its velocity and acceleration when it reaches its maximum altitude? What is its acceleration just before it hits the ground? Submitted by James P. 4 m / s 2 + 2-9. Science; Physics; Physics questions and answers; You throw a ball vertically upward so that it leaves the ground with velocity 6. 17}, which gives us the maximum height of the booster. 8. 0 s Sep 29, 2015 · I found 6s and 46m The ball starts with initial velocity v_i=30m/s and it reaches maximum height where the velocity will be zero, v_f=0. This means that its velocity is zero at that instant. (a) What is its velocity when it reaches its maximum altitude? magnitude 0 m/s direction ---Select 7 (b) What is its acceleration at this point? magnitude m/s2 direction --Select- (c) What is the velocity with which it returns to ground level? magnitude m/s direction Question: 6. As calculated, the rocket reaches a maximum height of 2400 meters. Then its engine fails, and the rocket proceeds to move in free fall. (a) What is its velocity when it reaches its maximum altitude? magnitude m/s direction (b) What is its acceleration at this point? magnitude m/s^2 Direction: Up Down No direction (c) What is the velocity with which it returns to ground level? A catapult launches a test rocket vertically upward from a well, giving the rocket an initial speed of $$80. Does its acceleration increase, decrease, or Transcribed Image Text: You throw a ball vertically upward so that it leaves the ground with velocity 3. (a) When the ball reaches its maximum altitude, what is its velocity?; (b) When the ball reaches its maximum altitude, what is its acceleration?; (c) What is the acceleration of the ball just before it hits the ground? Question: You throw a ball vertically upward so that it leaves the ground with velocity 5. (a) What is its velocity when it reaches its maximum altitude? magnitude 0 Correct: Your answer is correct. When the ball reaches its maximum altitude, its velocity is, An object is in free fall as soon as it is released, whether it is dropped from rest, thrown downward, or thrown upward. Does its acceleration increase, decrease, or Sep 5, 2018 · During the ball's upward motion, its velocity decreases until it reaches its highest point where its velocity becomes zero. (a) What are its veloc- ity and acceleration when it reaches its maximum altitude? (b) What is the acceleration of the ball just before it hits the ground? 6. (a) What is its velocity when it reaches its maximum altitude? (a) What are its velocity and acceleration when it reaches its maximum altitude? (b) What is the acceleration of the ball just before it hits the ground? A ball is thrown vertically upward. (a) What is its velocity when it reaches its maximum altitude? (b) What is its acceleration at this point? (c) What is the velocity with which it returns to ground level? (d) What is its acceleration at this point? What are its velocity and acceleration when it reaches its maximum altitude? You throw a ball vertically upward so that it leaves the ground with velocity +5. (a) What is its velocity when it reaches its maximum altitude? magnitude m/s direction ---Select--- v (b) What is its acceleration at this point? magnitude I m/s² direction ---Select--- V (c) What is the velocity with which it returns to ground level? magnitude velocity and acceleration when it reaches its maximum altitude? (b) What is the acceleration of the ball just before it hits the ground? PROBLEMS 8. What is its acceleration when it reaches its maximum altitude? Step 1. 8 m/s^2. A ball is thrown vertically upward. (a) What is its velocity when it reaches its maximum altitude? magnitude m/s direction --Select--- (b) What is its acceleration at this point? magnitude direction -Select- m/s2 (c) What is the velocity with which it returns to ground level? magnitude m/s direction Oct 11, 2023 · Final answer: The ball's velocity when it reaches its maximum altitude is 0 m/s. (a) What is its velocity when it reaches its maximum altitude? (b) What is its acceleration at this point? (c) A ball is thrown from the ground level with an x-velocity of 25 m/s and a y-velocity of 45 m/s. A catapult gives it an initial speed of 80. e. This is because as the ball reaches its maximum height, it stops moving vertically before falling back down due to gravity. (a) What is its velocity when it reaches its maximum altitude? You throw a ball vertically upward so that it leaves the ground with velocity 6. that the acceleration of car A is greater than that of car If the velocity of a particle is nonzero, can the particleÕs acceleration be zero? Explain. What is its acceleration at maximum altitude? You throw a ball vertically upward so that it leaves the ground with velocity +5. , Supposed that an object is moving with a constant velocity. Solution for (b) From the information now in hand, we can find the final horizontal and vertical velocities \(\displaystyle v_x\) and \(\displaystyle v_y\) and combine them to find the total velocity v . 2 m/s by a catapult and accelerates upward at 4. (a) What is the initial speed of the ball? (b) When the ball is near its maximum height it experiences a brief gust of wind that reduces its horizontal velocity by 1. Explanation: When a ball is thrown vertically upward, it experiences a constant acceleration due to gravity. 59 m/s. You throw a ball vertically upward so that it leaves the ground with velocity +5. This velocity you really degrees are in the maximum height at and becomes zero he had after that it will return towards or is no position and its velocity increases from the maximum height. Sep 3, 2004 · In summary, the conversation discusses the problem of finding the time, maximum altitude, and velocity of a test rocket that is fired vertically upward from a well and then goes into free fall. Mar 18, 2023 · 2. Make a statement concerning its acceleration. At the maximum altitude, the ball's acceleration is still negative (downward) due to gravity, but its magnitude is equal to the acceleration due to gravity at that altitude. (a) What is its velocity when it reaches its maximum altitude? magnitude m/s direction ---Select-- (b) What is its acceleration at this point? magnitude direction --Select- m/s2 (c) What is the velocity with which it returns to ground level? magnitude m/s direction --Select. 8- b 9. 24, 2022 04:19 a. (a) What is its velocity and direction when it reaches its maximum altitude? magnitude m/s (b) What is its acceleration and direction at this point? magnitude m/s^2 (c) What is the velocity and direction with which it returns to ground level? (a) What is its velocity when it reaches its maximum altitude? and direction? (b) What is its acceleration at this point? and direction? (c) What is the velocity with which it returns to ground level? and direction? What are its velocity and acceleration when it reaches its maximum altitude? What is its acceleration just before it hits the ground? There’s just one step to solve this. 353 direction down m/s2 (c) What is the velocity with which it returns to ground level? magnitude -5. 15 m/s. 80 m/s^2. We know that at the maximum height, the velocity of the object becomes zero. (a) What is its velocity when it reaches its maximum altitude? (b) What is its acceleration at this point? (c) What is the velocity with which it returns to ground level? (d) What is its acceleration at this point? Aug 4, 2023 · The velocity of the ball when it reaches its maximum altitude is zero. 10 m/s2 until it reaches an altitude of 950 m. (a) What is its velocity when it reaches its maximum altitude? magnitude o m/s direction down (b) What is its acceleration at this point? magnitude 1. Answer and Explanation: 1 Let's say that the upward direction is positive, and the downward direction is negative. Here, v’ is the velocity at the maximum height, the value of which is zero, g is the gravitational acceleration, and h’ is the altitude. 00 m/s^2 until it reaches an altitude of 1000m. a. So, the velocity at maximum altitude is: $$\boxed{0\,\text{m/s}}$$ Nov 19, 2023 · Let's start with part (a), finding the time it takes for the ball to reach its maximum altitude. 64 m/s (a) What is its velocity when it reaches it:s maximum altitude? magnitude direction | Select m/s (b) What is its acceleration at this point? magnitude direction Select m/s (c) What is the velocity with which it returns to around level? magnitude directionSelect m/s (d) A ball is thrown vertically upward. 8. m. A catapult gives it initial speed 80. 0 m/s. What is its velocity when it reaches its maximum altitude? magnitude 0 direction no direction What is Its acceleration at this point? magnitude 9 8 m/s^2 direction down What is the velocity with which it returns to ground level? Question: 1. Without an effect from the wind, the ball would travel 60. Therefore, the acceleration at the maximum altitude of the ball becomes zero. 0 s, and (d) 0 to 5. (a) What is its velocity when it reaches its maximum altitude?magnitudemsdirection(b) What is its acceleration at this point?magnitudems2direction(c) What is the velocity with which it returns to ground level?magnitudemsdirection(d) What is its acceleration at this The highest point in any trajectory, the maximum height, is reached when v y = 0 v y = 0; this is the moment when the vertical velocity switches from positive (upwards) to negative (downwards). What are its velocity and acceleration when it reaches its maximum altitude? What is its acceleration just before it hits the ground? A ball is thrown vertically upward. (a) What are its velocity and acceleration when it reaches its maximum altitude? (b) What is the acceleration of the ball just before it hits the ground? - PROBLEMS 8. 64 m/s. 00 m/s . Question: 6. Question: You throw a ball vertically upward so that it leaves the ground with velocity 6. We can use the equation v_f = v_i + at, where v_f is the final velocity, v_i is the initial velocity, a is the acceleration, and t is the time. (a) What is its Jun 22, 2024 · At the maximum altitude, the ball's velocity is zero and its acceleration is equal to the acceleration due to gravity, pointing downwards. 00 m/s? until it reaches an altitude of 1000 m. 3 s) (c) What is the velocity of the rocket at the moment it hits the ground? (answer: - 157 m/s) (d) What is the total flight time of the rocket from the moment it is launched until the moment it hits the ground? Jan 28, 2024 · We know the velocity is zero at the maximum position within the acceleration interval; thus, the velocity of the booster is zero at its maximum height, so we can use this information as well. Question: At time to a ball is shot upward from the ground with an initial velocity of vo. b. 37 m/s. (a) What is its velocity when it reaches its maximum altitude? (b) What is its acceleration at Oct 23, 2022 · Therefore, its velocity will be 0 m/s. When the ball is thrown upward, its initial velocity is positive (upward direction). Feb 3, 2020 · For a given projectile, the velocity of the projectile when it reaches its maximum height is 0 m/s. 00 m/s 2 until its engines stop at an altitude of 150 m. (a) What is its velocity when it reaches its maximum altitude? (b) What is its acceleration at this point? (c) What is the velocity with which it returns to ground level? (d) What is its acceleration at this point? Please Explain Acceleration due to Gravity: When an object is thrown upwards, it returns back to the ground. At that point, its engines fail and the rocket goes into free fall, with an acceleration of -9. Question: You throw a ball vertically upward so that it leaves the ground with velocity 2. (a) What is its velocity when it reaches its maximum altitude?magnitude m/sdirection ---Select--- Step 1/4 (a) When the ball reaches its maximum altitude, its velocity will be 0 m/s because it will momentarily stop before falling back down. 65 m/s. (b) What is its acceleration at this point? magnitude -9. (a) What is its velocity when it reaches its maximum altitude? magnitude m/s direction --Select--- upi > nodirection , down (b) What is its acceleration at this point? magnitude direction --Select--- m/s2 (c) What is the velocity with which it returns to ground level? Your solution’s ready to go! Oct 3, 2019 · Find (a) the position and velocity of the ball 1. 64 m/s. A tennis player moves in a straight-line path as shown in Figure P2. The maximum altitude is calculated as. Its acceleration remains constant at -9. 96 s in the air. 0 m/s$$ at ground level. 0 m below its starting altitude will spend 3. 44 m/s. (a) What is the maximum height reached by the rocket? (b) How long after lift-off does the rocket reach its maximum height? (a) What are its veloc-ity and acceleration when it reaches its maximum altitude?(b) What is the acceleration of the ball just before it hits theground Your solution’s ready to go! Enhanced with AI, our expert help has broken down your problem into an easy-to-learn solution you can count on. Just before it hits the ground, it also experiences an acceleration of -9. 0 s to 5. It accelerates with a constant upward acceleration of 2. 68 m/s. So any projectile that has an initial vertical velocity of 14. 00 s after it leaves your hand; (b) the velocity of the ball when it is 5. Step 3/4 3. 00 m/s. 0 s, (c) 1. Its engines then fire and it accelerates upward at 4. (a) What is its velocity when it reaches its maximum altitude? (b) What is its acceleration at this point? (c) What is the velocity with which it returns to ground level? (d) What is its acceleration at this point? (answer: 1260 m) (b) How much time does the rocket take to reach its maximum altitude? (answer: 32. What factors affect projectile motion? The main factor that could affect the motion of a projectile is friction. 80ms. does its acceleration increase, decrease, or 5. 8 m/s². The rocket is given an initial speed of 79. At that point its engines fail and the rocket goes into free fall, with an acceleration of -9. 8m/s^2 is slowing it down up to the maximum height where the ball finally stops; You can say that the final velocity depends upon the initial velocity AND the contribution of the acceleration that Apr 7, 2022 · (b) What is its maximum altitude? (c) Determine the velocity and acceleration of the ball at t = 2' 'ball is thrown vertically upward from the ground with an initial speed of 15 m/s. A model rocket is launched straight upward with an initial speed of 50. This is because You throw a ball vertically upward so that it leaves the ground with velocity 4. 74 m/s. Its velocity is zero at maximum altitude. Since acceleration is the rate of change of velocity, when the velocity is zero, the acceleration is also zero. The time interval delta t, is always positive. (a) What are its velocity and acceleration when it reaches its maximum altitude? (b) What is the acceleration of the ball just before it hits the ground? A ball is thrown vertically upward. (a) How long does it take the ball to reach its maximum altitude? (b) What is its maximum altitude? (c) Determine the velocity and acceleration of the ball at t = 2' acceleration of 8. Question: You throw a ball vertically upward so that it leaves the ground with velocity 15. Find her average velocity in the time intervals from (a) 0 to 1. What are its velocity and acceleration when it reaches its maximum altitude? You throw a ball vertically upward so that it leaves the ground with velocity +5. (a) What is its velocity when it reaches its maximum altitude? magnitude |m/s direction --Select--- (b) What is its acceleration at this point? magnitude |m/s² direction --Select-- (c) What is the velocity with which it returns to ground level? m/s direction -Select--- v magnitude The engines then fire, and the rocket accelerates upward at 4. What happens to the ball’s velocity while the ball is in the air? b. 11 m/s. (a) For what time interval is the rocket in motion above the ground? (b) What is its maximum altitude? (c) What is its velocity you throw a ball vertically upward so that it leaves the ground with velocity 5. What is its acceleration when it reaches its maximum altitude? d. At its maximum altitude, the ball's velocity becomes zero. The velocity decreases on the way up, is zero at the top, and then increases on the way down. DETAILS You throw a ball vertically upward so that it leaves the ground with velocity 2. This is because the ball has reached its highest point and is about to change direction and start moving downward. For the rocket, this happens when all upward velocity ceases momentarily before gravity begins to pull it down. Feb. 05 m/s. 00 s$$ the rocket moves along its initial line of motion with an acceleration of $$30. 00 m/swhat is its velocity when it reaches maximum altitude Your solution’s ready to go! Enhanced with AI, our expert help has broken down your problem into an easy-to-learn solution you can count on. 15 m/s direction down The rocket engine immediately starts a burn, and for $$3. (a) What is its velocity when it reaches its maximum altitude? magnitude m/s direction (b) What is its acceleration at this point? magnitude direction m/s2 (c) What is the velocity with which it returns to ground level? magnitude direction m/s (d A ball is thrown vertically upward. In order to turn around, the ball’s velocity must pass through zero. what is its velocity when it reaches its maximum altitude? c. (a) What is its velocity when it reaches its maximum altitude?magnitude 0 Correct: Your answer is correct. 00 m/s^2 until it reaches an altitude of 1000 m. Feb 3, 2020 · a. The engines then fire, and the rocket accelerates upward at $$4. The initial velocity of the ball is 5. What are its velocity and acceleration when it reaches its maximum altitude? A ball is thrown vertically upward. A test rocket is fired vertically upward from a well. This acceleration causes the ball’s velocity to decrease at a constant rate until it reaches maximum altitude, at which point it turns around and starts to fall. 85 m/s. Let's look at another question: what is the maximum altitude reached by the projectile? Let's think about what is unique about the point where the projectile is at its maximum altitude: the \(y\) component of the velocity is momentarily zero at that point. Just before the ball hits the ground, its acceleration remains constant at approximately 9. The time age Learning Question: You throw a ball vertically upward so that it leaves the ground with velocity 4. (a) What is its velocity when it reaches its maximum altitude? Click here👆to get an answer to your question ️ You throw a ball vertically upward so that it leaves the ground with velocity + 5. The equation for the distance traveled by a projectile being affected by gravity is sin(2θ)v 2 /g, where θ is the angle, v is the initial velocity and g is acceleration due to gravity. Is there we throw this ball in upward direction? I'M assuming that we throw this ball at the speed of the ball attends its maximum height. 0 m horizontally. 80 m/s2. (a) What is its velocity when it reaches its maximum altitude? (b) What is its accel. Aug 4, 2023 · At the maximum altitude, the ball momentarily comes to a stop before falling back down. Question: 8. 8 m/s^2 at maximum altitude. 32 m/s. The velocity at the maximum altitude is always 0 m/s for a ball thrown vertically Objects at its maximum altitude have zero velocity and the magnitude of the velocity at a particular height is the same as it goes up or down. what is its acceleration just before it hits the ground? e. What is its velocity when it reaches its maximum height? Velocity is 0 m/s at its highest point. (a) What are its velocity and acceleration when it reaches its maximum altitude? (b) What is the acceleration of the ball just before it hits the ground? There are 2 steps to solve this one. (a) What is its velocity when it reaches its maximum altitude? (b) What is its acceleration at this point? (c) A ball is thrown vertically upward. Also, for any given projectile, the acceleration at maximum height is 0 m/s². Oct 6, 2016 · At the highest point of the ball's trajectory, the ball momentarily stops moving vertically. When the ball reaches its maximum height, its final velocity will be 0 m/s. 0 s, (b) Oto 4. (a) What are its velocity and acceleration when it reaches its maximum altitude? This answer has not been graded yet. 6. You throw a ball vertically upward so that it leaves the ground with velocity 15. 00 m above the railing; and (c) the maximum height reached and the time at which it is reached. At that point its engines fail, and the rocket goes into free fall, with an acceleration of -9. A ball is thrown vertically The initial velocity is you. (b) What is the acceleration of the ball just before it hits the ground? Assume that the ball is thrown vertically upward with initial velocity of v 0 v_0 v 0 , then start to decrease during the path of the throwing until it reaches the maximum height, where the ball stopped for a very short time (the velocity is zero at the maximum height \textbf{the velocity is zero at the maximum height} the velocity is zero at A ball is thrown vertically upward. 3 m/s and lands 20. 50 m/s. 6 m. 8 Incorrect: Your answer is incorrect. c. Figure CQ2. 00 s and 4. What is its velocity when it reaches its maximum altitude? c. d. Jul 22, 2024 · We know that when an item reaches its maximum height, its velocity becomes zero. The engines then fire, and the rocket accelerates upward at 4. 55 m/s.