A bullet moving horizontally to the right (+x direction) with a speed of 500 m/s strikes a sandbag and penetrates a distance of 10.0 cm. What is the average acceleration, in m/s2, of the bullet?
Physics · High School · Thu Feb 04 2021
Answered on
To find the average acceleration of the bullet, we need to use the kinematic equation that relates initial velocity (v_i), final velocity (v_f), acceleration (a), and distance (d). Since the bullet is coming to a stop, v_f is 0 m/s. We are given:
- The initial velocity, v_i = 500 m/s (in the +x direction) - The final velocity, v_f = 0 m/s (since the bullet stops) - The distance penetrated, d = 10.0 cm = 0.1 m (we need to convert cm to m)
We'll use the following kinematic equation:
v_f^2 = v_i^2 + 2ad
Solving for acceleration (a):
a = (v_f^2 - v_i^2) / (2d)
We can plug in our values now to calculate the acceleration:
a = (0^2 - (500 m/s)^2) / (2 * 0.1 m) a = (-250000 m^2/s^2) / (0.2 m) a = -1250000 m/s^2
The acceleration is negative because it’s a deceleration - the bullet is slowing down.
So the average acceleration of the bullet while it's in the sandbag is -1,250,000 m/s².