Question

acceleration homework

1. a car accelerates from 0 m/s to 20 m/s in 10 seconds. what is the acceleration of the car?
2. a jogger goes from rest to 2 m/s in 5 seconds. what is the jogger’s acceleration?
3. you slam on your car’s brakes and go from 25 m/s to 0 m/s in 10 seconds. what is the car’s acceleration?
4. a cheetah changes its velocity by 10 m/s in 2 seconds. what is the acceleration of the cheetah?
5. you are riding your motorcycle with a velocity of 15 m/s before slowing down to 5 m/s in 5 s. what is the acceleration of your motorcycle?

Explanation:

Problem 1

Step1: Recall acceleration formula

Acceleration \( a = \frac{v_f - v_i}{t} \), where \( v_f \) is final velocity, \( v_i \) is initial velocity, \( t \) is time.

Step2: Substitute values

\( v_i = 0 \, \text{m/s} \), \( v_f = 20 \, \text{m/s} \), \( t = 10 \, \text{s} \). So \( a = \frac{20 - 0}{10} = 2 \, \text{m/s}^2 \).

Step1: Use acceleration formula

\( a = \frac{v_f - v_i}{t} \), initial velocity \( v_i = 0 \, \text{m/s} \) (rest), \( v_f = 2 \, \text{m/s} \), \( t = 5 \, \text{s} \).

Step2: Calculate acceleration

\( a = \frac{2 - 0}{5} = 0.4 \, \text{m/s}^2 \).

Step1: Apply acceleration formula

\( a = \frac{v_f - v_i}{t} \), \( v_i = 25 \, \text{m/s} \), \( v_f = 0 \, \text{m/s} \), \( t = 10 \, \text{s} \).

Step2: Compute acceleration

\( a = \frac{0 - 25}{10} = -2.5 \, \text{m/s}^2 \) (negative for deceleration).

Answer:

\( 2 \, \text{m/s}^2 \)

Problem 2