Upgrade to remove ads
Only $35.99/year

Science Chapter 4

Terms in this set (46)

energy
the ability to cause change or do work
system
anything around you which can imagine a boundary
what happens when one system does work on another system
energy is transferred from one system to the other
6 different forms of energy
mechanical, electrical, chemical, radiant, sound, thermal
is energy from the sun and energy from the food you eat the same?
yes they are different forms of the same thing
kinetic energy
energy due to motion
formula for kinetic energy
KE=1/2mv^2
2 variables of kinetic energy
kg and m/s direction
potential energy
energy stored due to the interactions between objects
elastic potential energy
the energy that is stored by stretched or compressed objects
chemical potential energy
energy due to chemical bonds
where is stored energy
in the chemical bonds between atoms
gravitational potential energy
energy that is due to the gravitational forces between objects
another description of gravitational potential energy
energy an object has due to its mass and position (height off the ground)
variables to calculate GPE
mass-kg gravity-N/kg height-m
GPE formula
mgh
law of conservation of energy
energy cannot be created nor destroyed, but can change form
mechanical energy
the sum of the KE and PE in a system
mechanical energy includes...
kinetic energy, elastic potential energy, and gravitational potential energy
an apple that falls off of a tree ________ GPE
loses
as an apple falls from a tree it _______ kinetic energy
gains
potential and kinetic energy can be _________
converted
why does a person on a swing come to a stop
because it takes continuous mechanical energy (pumping the swing) to keep swinging. The air resistance and friction transform mechanical energy into thermal energy.
a light bulb is a device that transforms _________
energy
fuel stores energy in the form of ____________
GPE
a car engine transforms chemical potential energy into ____________ and ________ energy into ___________ energy
thermal, sound, mechanical
chemical energy in a car _______ get converted into mechanical energy
does not
how efficient is the chemical energy for fuel in a car
4% efficient
every green plant converts ________ into ________
radiant energy, chemical potential energy
power
the amount of work being done over time
energy from food is often measured in...
calories
every gram of fat supplies your body with...
10 calories
every gram of protein and carb you eat supplises your body with
5 calories
calorie
A unit of heat used to measure the energy your body uses and the energy it receives from food
alternate definition of power
the amount of work done over a certain amount of time
rate at which work is done
formula for power
P=W/t
standard unit to measure power
watts
british thermal units
1 Btu (1055 watts)-power of a heating or cooling device
Horsepower
1 HP (746 watts)-power of an engine
1 calorie=
4.184 joules
sound energy
Energy caused by an object's vibrations
radiant energy
energy carried by light
electrical energy
energy of moving electrons
nuclear energy
Energy stored in the nucleus of an atom
thermal
related to heat or temperature
chemical energy
potential energy stored in chemical bonds
Other sets by this creator