Question

8. A car moving at 35 m/s has 675 joules of KE. What is the mass of the car?

Answer 1

Kinetic energy is the energy possessed by a body in motion while potential energy is the energy of a body at rest.
Kinetic energy is given by E=1/2MV² where M is the mass of the body while V is the velocity of the body. 
To get mass we can use the formula M= 2 Ek/V² (Making M the subject)
hence mass  = (2 ×675)÷35²
                     = 1.102 kg