Question

A golf ball starts with an initial velocity of 100m/s and slows at a constant rate of -8m/s2, what is its final velocity after 2s?

Vf = Vi+at

A. 20 m/s

B. 84 m/s

C. 16 m/s

Answer 1

Answer: B. 84 m/s

Step-by-step explanation:

Uniform Speed Motion

It's a type of motion in which the velocity of an object changes by an equal amount in every equal period of time thus, the acceleration is constant.

Being a the constant acceleration, vo the initial speed, vf the final speed, and t the time, the final speed is calculated as follows:

`v_f=v_o+at`

The golf ball starts with an initial speed of 100 m/s and slows down at a=-8\ m/s^2. We are required to find the final speed at t=2 s:

`v_f=100-8*2=100-16`

`v_f=84\ m/s`

Answer: B. 84 m/s