Solve the following word problems using the kinetic and potential energy formulas. Be sure to SHOW YOUR WORK!!

KE = PE = ×× = ⁄

Example 1

A group measures the speed of a 0.1 kg car at 2.5 m/s. What is the kinetic energy of the car?

KE = 12 × 0.1 ×(2.52) {When something is square it is multiplied by itself (2.5 x 2.5)

KE = 0.05 ×6.25

KE = 0.3125 Joules

Example 2

You are on rollerblades at the top of a 10 m hill. Your mass is 60 kg. What is your potential energy?

PE = 60 x 10 x 10

PE = 6000 J

1. Determine the kinetic energy of a 1000 kg roller coaster car that is moving with a speed of 20.0 m/s.

2. Missy Diwater a platform diver, had a kinetic energy of 15,000 J prior to hitting the bucket of water. If Missy’s mass is 50 kg, then what is her speed?

3. A cart is loaded with brick and pulled to the top of a ramp. If the mass of the loaded cart is 3.0 kg and the height of the plane is 0.45 meters, what is the potential energy of the loaded cart?

4. A 75 kg refrigerator is located 300 meters above the ground. What is the potential energy of the refrigerator?

5. The potential energy of a 40 kg cannon ball is 14,000 J. How high was the cannon ball to have this much potential energy?

when the use of electricity burdens the fuse and miniarure circuit beakers and there is a possibility of a fuse then they automatically cut off the electricity supply to your homes and after you fix the problem u jzt switch it on and it continues the supply of electricity to ur homes

the motion of a pendulum is a classic example of mechanical energy conservation. a pendulum consists of a mass (known as a bob ) attached by a string to a pivot point. as the pendulum moves it sweeps out a circular arc, moving back and forth in a periodic fashion.

russian is not my first language, so i'm afraid i can't write out an answer in russian, but hopefully you can find a way to do so. here's my best translation of the problem: you're given a plot of a particle's position in one-dimensional space over time, and you're asked to find either the total distance traveled by the particle after 6 seconds had elapsed, or the total displacement of the particle after 6 seconds.

if you want the total distance traveled, you would first need to determine the particle's velocity as a function of time, then integrate that over the 6-second interval. we know the position function is quadratic with roots at 0 and 6, so we have

where is unknown. because the position is parabolic, there is symmetry about the midpoint at , and we know that

so that the position function is

which means the velocity is

then the total distance traveled is

so the total distance traveled is 20 m.

on the other hand, if you want to find displacement: the particle starts at and ends at , so its displacement is 0.