Final Review Flashcards
What is the definition of work?
Work is the transfer of energy when an applied force moves an object over a distance
What is the purpose of simple machines?
To make work easier
What is a pulley, How does it make work easier?
A wheel with a grove for a rope to move the pulley. It makes work easier by changing the direction of the applied force
What is a example of a pulley?
Crane
What is a screw?
An inclined plane wrapped around a cylinder
What is a example of a screw?
Jar lid
What is a wedge?
A modified inclined plane that also increases the distance by which the effort force is applied
What is a example of a wedge?
Axe
What is an inclined plane?
A device that increases the distance by which the effort force is applied
What is a example of a inclined plane?
Ramp
What is a lever?
A board or bar that sits on a fixed point called a fulcrum
What is an example of a lever?
hammer
What is a gear (wheel and axle)?
A wheel with teeth around the perimeter attached to a rod decreases the effort force applied and increases the distance that force is applied over
What is a example of a gear?
Bike wheels
What is the formula for work?
W=FxD
What is the formula for power?
P=W/T
What is the law of conservation of energy?
State that energy can not be created nor destroyed
What is kinetic energy?
Energy that an object possesses due to its motion
What is a example of kinetic energy?
A person walking
A soaring baseball
Wheels on a bike going round and round
What factors impact kinetic energy?
Mass and speed
What is the formula for kinetic energy?
1/2 m x v
What is potential energy?
energy that an object has at rest; stored energy that can be used for later
What is a example of Potential energy?
1.A sling being pulled to its launch position
2.Water behind a dam
3. A yoyo before it is released
4. Energy found in food molecules before eaten
What factors impact potential energy?
the height above the reference point, acceleration due to gravity,mass,
gravitational potential energy
What is the gravitational potential energy formula?
GPE= m x g x h
What are some pros of Nuclear Energy?
Lasts a long time
Clean Energy source
Pays itself back
Creates job
provides continuous electricity
What are the cons of Nuclear energy?
Very high upfront costs
Nuclear waste is bad for the environment and can be radioactive even after it is useful
malfunctions can be catastrophic
Can be stable and unsafe process
What is distance?
How far an object travels or how apart the position are
What is displacement?
Change in position
What is acceleration?
Change in velocity in a given amount of time