Work and Energy
Energy
Work and Power
Work--> Kinetic Energy
Work & Potential Energy
100
Define: Work
the change in energy of an object done by applying a Force to an object causing it to have displacement
100

Give an example of an object with gravitational potential energy

Answers Vary (e.g, A book on a table)

100

What is the SI unit for power?

Watts

100
What is Kinetic Energy?
Energy of a moving object
100

How much work is done if Zion pushes a force of 600N against the wall for 3mins?

0J (No work is done)

200

What is the formula for work?

W=F(D) D=Distance

200

Which form or forms of energy does a ball falling through the air possess

gravitational potential energy and kinetic energy

200
What is the difference between energy and power?
work and energy don't involve time, but power does
200
What is the formula for KE?
KE=1/2MV^2 (Joules)
200
Define gravitational potential energy?
Energy of an object placed at a height above a reference level
300

When is work done and not done during the lift of a military press?

When the object is being lifted, not at the top when it is still.

300

A pin ball being pushed into action by a spring. 

mechanical and kinetic (maybe gravitational too!)

300

What is the formula for power

P=W/T

300
Can KE ever be negative?
No, the velocity is squared-->always positive
300

What is the formula for gravitational potential energy?

PE=mgH

400

What is an example of when force is applied but no work is done? 

push on wall or other 

400

A hydroelectric dam involves what kinds of energy.

Kinetic, mechanical, electric

400

Who does more work? Spencer walking up the 20 m high staircase carrying his backpack in 10 seconds, or John running up the same staircase carrying a backpack in 3 seconds?

John

400

Where is kinetic energy of a pendulum bob on a string the highest?

At the bottom (middle position)

400

An object has a mass of 250 kg. It is 20 m above the ground. What is the PE?

49000J

500

1) How much work is done if I push a 100N crate across the floor with a force of 50N for a distance of 100cm?

1) W=F(D) 50(1)=50 J

500

What is the law of conservation of energy.

Energy is never created, lost, or destroyed. Only transformed.

500

A runner runs up a flight of stairs using 200J of work in 10 sec. What is the Power?

Power: P=W/T= 20 Watts

500
What happens if you double velocity and triple the mass?
Proportional reasoning-KE=1/2MV^2=3M(4V)=12KE
500
A 45 kg skier starts off from rest at the top of the hill 85 m high. How much PEG does the skier have at the top?
PE=mgh =60Kg(10m/s^2)(10m)
M
e
n
u