well, I get 1.47*10^2 Joules
Yes, work done = change in kintic energy
A pitcher throws a fast ball with a speed of 45m/s. The ball has a mass of 0.145kg. How much a) kinetic energy is given to the ball and b)What work was done in throwing the ball?
Vo=45 m/s
Mass= 0.145kg
A) KE?
KE= 1/2mV^2
A) 1.5x10^2 kg*m/s
B) WK=Change in KE
but I'm stuck not sure if these are the correct equations to use. Or if they are how to find work since I don't know the F or the D
6 answers
thank you but looking at my notes it says work = Fcos thata d buthow do plot F and D that I do not have
work here is equal to the KE you calculated, you do not need force and distance the hand traveled.
so a and b are equal to the same Joules? Sorry I'm so confused
or do I need to use one of these equations
Fcos thata d= 1/2mVf^2-1/2mVo^2
or
F*D=1/2mVf^2-1/2mVo^2
Fcos thata d= 1/2mVf^2-1/2mVo^2
or
F*D=1/2mVf^2-1/2mVo^2
got it thanks for your help
1 answer