Question

A girl pulls a sled with a force of 15 N over a distance of 3 m. What is the kinetic energy of the sled after she pulls it? Assume there is no friction.

Answer 1

Answer:

Kinetic energy, KE = 45 J

Explanation:

It is given that,

Force applied by girl on a sled, F = 15 N

It moves a distance, d = 3 m

We need to find the kinetic energy of the sled after she pulls it. We know that the work done is equal to the change in kinetic energy

$W=\Delta E=K_f-K_i$

$K_i=0$ (initial at rest)

$KE=W=F\times d$

$KE=15\ N\times 3\ m=45\ J$

So, the kinetic energy of the sled after she pulls it is 45 J. Hence, this is the required solution.

Answer 2

The answer is 45 because you multiply 15 x 3