Question

Bending is a winter sport in which participants push a 15 kg rock across a horizontal snow patch. In 3.0 seconds, a bender accelerates a rock from rest to 4.0 m/s. What is the average power of the bender for accelerating the rock?

Answer 1

We can use the formula for average power:

P = W / t

where W is the work done and t is the time taken. The work done can be calculated using the formula:

W = (1/2) * m * v^2

where m is the mass of the rock and v is its final velocity. Substituting the given values:

W = (1/2) * 15 kg * (4.0 m/s)^2 = 120 J

Substituting the given value of time:

t = 3.0 s

Now we can calculate the average power:

P = W / t = 120 J / 3.0 s = 40 W

Therefore, the average power of the bender for accelerating the rock is 40 watts.