Question

Suppose a moving object has 2000 J of kinetic energy. If its mass is 40 kg, what is its speed?

a. 10 m/s
b. 100 m/s
c. 7.07 m/s
d. 44.72 m/s

Answer 1

What is the formula for kinetic energy?

Answer 2

Ya. With the K.E formula, substitute the available values and find the non available value.

Answer 3

use KE=1/2*m/v^2\[1/2 mv ^{2}\]

Answer 4

ans wil be 10 m/s (a)

Answer 5

The Formula for Kinetic Energy is 1/2 m v^2
So set 1/2 m v^2 = 2000 Joules
Solve for v
\[1/2mv^2=2000 J\]\[mv^2=4000 J\]\[v=_{4000/40}^{1/2}\]
10 m/s

Answer 6

Ignore the v equation... I give up on the stupid thing for writing roots.