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Vocab
Work
Energy
Calculating Work, Power & Energy
Misc.
100

The product of force, displacement, and the cosine of the angle between them.

Work

100

What does work require?

Force, displacement, and that they are parallel.

100

A 7 kg object is motionless.  Calculate kinetic energy.

0 J
100

A person walking their dog pulls on their leash with a force of 12 N for 5 m. What is the work done on the dog?

60 J

100

What is the law that states that energy cannot be created or destroyed but can be changed from one form to another

The law of conservation of energy.

200

The energy stored in a stretched or compressed object.

Elastic Potential Energy
200

Work is positive when...

The force and displacement are in the same direction.

200

What is the formula for Kinetic Energy?

KE=1/2 m v^2

200

A 2.1 kg rock is being held at a height of 8.7 m.  Calculate it's kinetic energy just before hitting the ground.

179 J
200

What is the potential energy of a 4kg orange cat on top of a 3 meter high bookshelf?

GPE= (4kg)(10m/s^2)(3m)

GPE=120J

300

Energy of motion

Kinetic Energy

300

Is work a vector or scalar quantity? Why?

A scalar quantity because it has no direction, only a magnitude.

300

Name for energy that comes from heat

What is thermal energy?

300

A 5 kg rock is raised 30 m above the ground level. How much work is done to lift it?

W= 1500 Joules

300

A 1500 kg car is being pushed down a road at a speed of 1.4 m/s.  How much work must be done to increase the speed to 1.9 m/s

1237.5 J

400

The rate at which work is done.

Power

400

Energy - Work Theorem states that the work done an object equals the change in its ________

Kinetic Energy

400

How does potential energy differ from kinetic energy?

Potential energy is energy stored while kinetic is energy of motion.

400

Calculate the work done by a 47 N force pushing a pencil 0.26m

12 J

400

Steph is carrying her book across the room by balancing the book steady on her hand. Is work being done? Why or why not?

No, the force and displacement are not parallel.

500

A unit of power which equals to one joule per second

Watts

500
If the force applied to an object that is moved is quadrupled but moved for half the original distance, what happens to the work done?
Twice the Work
500

A 2.9 kg object has 656 J of kinetic energy. Calculate velocity.

21.3 m/s

500

A 60 W light bulb runs for 5 secs. How much energy does it use? 

300 J

500

A 2,500 kg race car accelerates from rest to 35 m/s in 7.3 s.  What is the power output of the engine?

209,763 W