As a woman walks, her entire weight is momentarily placed on one heel of her high-heeled shoes. This creates quite a large pressure on the ground; in fact, in the early days of commercial flight, women were not allowed to wear high-heeled shoes because aircraft floors were too thin to withstand such large pressures. Calculate the pressure, in pounds per square inch, exered on the floor by the heel if it has an area of 1.45 cm2 and the woman's mass is 635 kg.

The experiments with static charges were done by:

A23 kg log of wood begins from rest, 300 m up a sluice (a water track used to transport logs, think of it as an inclined plane with negligible friction) inclined at 20° to the horizontal. after it reaches the flat waterway at the bottom it collides elastically with a 100 kg block of wood initially at rest near the base of the incline. (a) how long does it take the 23 kg log to travel down the incline? (b) what is the speed of the 23 kg log at the bottom of the incline? (c) what are the velocities of both blocks of wood after the collision? (d) what is the total kinetic energy before the collision? (e) what is the kinetic energy of the 23 kg log after the collision? (f) what is the kinetic energy of the 100 kg block of wood after the collision? (g) what is the total kinetic energy after the collision? (h) compare the total initial and total final kinetic energies. is this consistent with what you would expect for elastic collisions? explain!

Occurs when an energy source transfers heat directly to another subject space; an example would be an object becoming warm by sitting in the sunshine