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A uniformly accelerating rocket is found to have a velocity of 11.0 m/s when its height is 4.00 m above the ground, and 1.90 s later the rocket is at a height of 56.0 m. What is the magnitude of its acceleration?

User JARH
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2 Answers

5 votes

Final answer:

To find the magnitude of acceleration, we used the kinematic equation s = ut + ½at². We determined the displacement due to the initial velocity and the time interval, and then solved for acceleration to find that the rocket's magnitude of acceleration is 17.2 m/s².

Step-by-step explanation:

To calculate the magnitude of its acceleration, we can use the kinematic equations for uniformly accelerated motion along with the information provided about the rocket's velocity and positions at different times. We have two positions, 4.00 m and 56.0 m, and a time interval of 1.90 s. The rocket's velocity at the lower height is 11.0 m/s.

Step 1: Use the second kinematic equation

We will use the kinematic equation:
s = ut + ½at², where 's' is the displacement, 'u' is the initial velocity, 'a' is the acceleration, and 't' is the time.

Step 2: Set up the equation with the known values

Let's calculate the displacement (Δs): Δs = 56.0 m - 4.00 m = 52.0 m
Now put the known values into the equation: 52.0 m = (11.0 m/s)(1.90 s) + ½a(1.90 s)²

Step 3: Solve for acceleration 'a'

First, we calculate the distance traveled due to the initial velocity: (11.0 m/s)(1.90 s) = 20.9 m
Subtract this value from the total displacement to find the displacement caused by acceleration: 52.0 m - 20.9 m = 31.1 m
Rewrite the equation with this new information: 31.1 m = ½a(1.90 s)²
Now solve for 'a': a = (2 × 31.1 m) / (1.90 s)² = 17.2 m/s²

The magnitude of acceleration of the rocket is therefore 17.2 m/s².

User Joshua Obritsch
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4.5k points
2 votes

Answer:

17.23 m/s²

Step-by-step explanation:

Applying the equation of motion,

Δs = ut + 1/2at²..................... Equation 1

Where Δs = change in height of the rocket, u = initial velocity of the rocket, a = acceleration of the rocket, t = time

making a the subject of the equation,

a = 2(Δs-ut)/t²..................... Equation 2

Given: Δs = (56-4) m = 52 m, u = 11.0 m/s, t = 1.90 s.

Substitute into equation 2

a = 2[52-(11×1.9)]/1.9²

a = 2(52-20.9)/1.9²

a = 2(31.1)/3.61

a = 62.2/3.61

a = 17.23 m/s².

Thus the acceleration = 17.23 m/s²

User Nir
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