Work, Work, Work, Work, Work, Work
What are the conditions of doing work?
1. The direction of motion and force MUST be the same.
2. The object of which work is being done MUST move/travel a distance.
How many simple machines are there?
6
The definition for kinetic energy
Energy due to motion
A couch is pushed with a force of 100 N and moves 15m across the floor, how much work is being done in moving the couch?
Formula: Work = Force × Distance
1,500 Joules
If an object doesn't move, has work been done?
No
List the simple machines.
1. Lever
2. Pulley
3. Screw
4. Wheel and Axel
5. Wedge
6. Inclined Plane
The definition for potential energy
Energy that is stored due to the interactions between objects
A rollercoaster is at the top of a 70m hill and has a mass of 150kg. How much potential energy does this rollercoaster have? Remember gravitational acceleration on earth is 10m/s².
Formula: PE=mgh
105,000 Joules
If an object's direction of motion is moving south and the direction of the force being applied to it is also south, is work being done?
What is an example of a wedge?
Doorstop, knife, axe, etc.
What are the types of potential energies?
A car is traveling with a velocity of 35 m/s and has a mass of 1,200 kg. How much kinetic energy does the car have?
Formula: KE = 1/2m x V2
735,000 Joules
What is the unit of measurement for work?
Joules
How many classes of levers are there?
3
What is the law of conservation of energy?
Energy can't be created nor destroyed, transferred from one form to another, and that the amount of energy stays the same.
A stroller on top of a 21m hill has 1,600 joules of potential energy, how much does it weigh? Remember gravitational acceleration on earth is 10m/s². Round to the nearest hundredth.
PE = mgh
7.62kg
What is the formula to calculate work that has been done?
Work = Force x Distance
What is the definition of a screw?
an inclined plane wrapped in a spiral around the
cylindrical post
What is an example of chemical potential energy?
Batteries, wood (before it burns), metal outside (before it rusts)
A jogger running has 2,430 joules of kinetic energy and a velocity of 9m/s. How much is their mass?
KE= 1/2m x v2
60kg