Physical Science Test Review: Chapter 4, Sections 1-3
Section 2: What is the definition of kinetic energy?
the energy a moving object has because of its motion
Section 1: What is the definition of work?
the energy transferred when a force makes an object move a certain distance
Section 1: What are the 6 simple machines?
lever, wedge, pulley, incline plane, wheel and axle, screw
Section 2: What two things determine an object's GPE?
mass and height (gravity is always constant)
Section 2: What is the formula for kinetic energy?
1/2mv^
Section 1: What is the efficiency of a machine whose work output is 4 joules, and whose work input is 10 joules?
40%
Section 1: What is the definition of a compound machine?
a combination of two or more simple machines
Section 1: What is the definition of a machine?
a device that changes the force or increases the motion from work
Section 1: What 2 things are required for work to happen?
a force makes an object move, and the object moves in the direction of the applied force
Section 1: What is the definition of a simple machine?
a machie that does work with just one movement
Section 1: What is the definition of efficiency?
a measure of how much input work is changed into useful output work by a machine
Section 2: What is the definiton of a system?
anything that a boundary can be drawn around
Section 2: What are three forms of potential energy?
chemical, elastic, gravitational
Section 3: What is the definition of the law of conservation of energy?
energy cannot be created or destroyed
Section 3: What is the formula for power?
energy/time
Section 1: What are three ways machines are useful?
increase speed, change direction, increase force
Section 2: What is energy measured in?
joules
Section 2: What is the formula for GPE?
mgh
Section 1: Can efficiency be above 100%
no
Section 3: Does mechanical energy ever change?
no because the form the energy is in changes, but the total amount of energy remains the same
Section 1: If you are holding a stack of book in your arms without moving them, are you doing work?
no, there is no movement
Section 1: What is the formula for efficiency?
output work/input work x 100%
Section 2: What are some forms of energy?
radiant, electrical, chemical, thermal, kinetic, etc.
Section 2: What is the definition of potential energy?
stored energy due to position
Section 2: What is the definition of energy?
the ability to cause change
Section 3: What is the defintion of power?
the rate at which energy is converted
Section 1: What is the definition of mechanical advantage?
the ratio of output force to the input force
Section 3: What is the defintion of mechanical energy?
the total amount of potential and kinetic energy in a system
Section 2: How are energy and money alike?
they both can come in different forms, but still be the same amount
Section 3: When is kinetic energy the lowest/highest?
when GPE is the highest/lowest
Section 3: When is GPE the lowest/highest?
when kinetic energy is the highest/lowest