How do you find Work using only force?

Question

Currently, in high school Physics, been working on this one for about an hour now:

"A football player pushes a tackling dummy (mass = 70 kg) for 72 seconds. If he pushes with a

force of 82 N, what is his average power output?"

I know how to do everything but I'm stuck at a stand-still because I can't figure out how to get work with out distance.

I've been using w= f x d for work and p= w/t for power.

Answer 1

Hi

you have

m

t

f

v_i=0

so you have all what you need to calculate impulse

I =f.t

I= Δp= mv_f _ mvi

find v_f

_{then find KE}

KE= 1/2 mv²

work done equal chang in kinetic energy

then

power = W/t