Physics ~please help me!
posted by Isis on .
1.) A car (m=1200 kg) moves form 2.0 m/s to 15.0 m/s in 100 m.
a) What is the initial kinetic energy of the car?
b) What is the final kinetic energy of the car?
c) what is the net work applied to the car?
d) what force is applied to the car?
2.) A simple pendelum is 1.5 m long and has 3.0 kg bob attached.
a) how much work was done by the chain to pull the car to the top?
b) how much potential energy does it have to the top?
c) what is the total energy of the system?
d) how much kinetic energy does it have at the bottom?
>> FORMULAS <<
KE= 1/2 v^2 (kinetic energy)
PE=mgh (potential energy)
W= Fd (work equals force and distance)
~please help me!
a) (1/2) m v^2 = .5 * 1200 * 4 = 2,400 Joules
b) (1/2) m v^2 = .5 * 1200 *225 = 135,000 Joules
c) 135,000 - 2,400 = 132,600 Joules
d) Force * distance = 132,600
100 F = 132,600
F = 1,326 Newtons
how far do you lift the bob, up to horizontal? up to top ?