Weight (that's what the 500 N is) = (mass) x (gravity) .
On Earth, gravity = about 9.8 m/s² , so
500 N = (mass) x (9.8 m/s²) .
Divide each side by 9.8 m/s²:
Mass = (500 N) / (9.8 m/s²)
= 51 kg (rounded) .
<span>A lubricant such as oil, grease, graphite powder can reduce the friction between two surfaces. Or using metal balls to space them and reduce the contact surface area as used in ball bearings.</span>
If you measured all the energy related to motion and all the stored
energy in the particles of a substance, you would be measuring the thermal energy of the particles. If
there is movement of the particles, they are also releasing energy in the form
of heat.
The force of static friction keeps a stationary object at rest. Once the force of static friction is overcome, the force of kinetic friction is what slows down a moving object.
The physical law that explains that is the law of conservation of energy which states that he energy of an isolated sistem remains constant