The motion of roller coasters depends upon the conversion of potential and kinetic energy. a 100-kg car starts from rest at the top of a hill with a height of 50 m. which of the following is this car's kinetic energy at the bottom of the hill? 150 j 5000 j 49,000 j 98,000 j

The kinetic energy will be 49000[J]

Explanation:

This problem is the common use of energy conservation when the body is at the top at the point where its elevation is the highest (usually the lowest point is taken as the reference level) at that point the body will have the highest potential energy, then as the body descends its potential energy decreases but its kinetic energy begins to increase. By the time the body reaches the lowest point or reference point, its potential energy will be zero, but its maximum kinetic energy, as all potential energy has become kinetic energy.

Therefore:

This energy will be transformed into kinetic energy at the bottom of the hill.

waves moving from a fast medium to a slow medium will experience a reflection as light travels more slowly than red light. total internal reflection occurs when the critical angle is.

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me