Science Quiz 1

chapter 5.1-5.2

energy

is the ability to cause change, or the ability to do work.

Work-Energy Theorem

the amount of energy an object has is equal to the amount of work that is done on it.

Kinetic energy

 is the energy of a moving object

what are 2 factors that effect Kinetic energy of an object?

mass and speed

do faster moving objects have more or less Kinetic energy?

more (because you do more work on an object in order to make it move faster.)

do heavier objects have more or less Kinetic energy?

more (because you have to push/pull harder on them in order to make them move.)

potential energy

stored energy for later use.

what are the 3 different forms of potential energy?

Gravitational, elastic and chemical potential energy

Gravitational potential energy

is potential energy due to the position of an object. (

what happens when objects are higher obove the ground?

potencial to fall a farther distance

Elastic potential energy

is potential energy due to the material an object is made out of.

what makes an object have more Elastic potential energy?

if the object is Stretchy or squishy objects have the potential to snap back or recoil when you let go of them.

Chemical potential energy

s potential energy due to the bonds between atoms of an object

how is Chemical potential energy released?

The energy is released when these bonds are broken.  

What is the total amount of energy in an object?

(potential energy + kinetic energy) mechanical energy.

Sound energy

is energy carried by objects that vibrate or make sound

what can sound energy not travel through?

a completely empty space.

thermal energy (heat energy)

 is the sum of kinetic and potential energy of atoms and molecules in matter due to their motion

hotter objects have more…

kinetic energy (and faster moving molecules) than cold objects do.

electric energy

is the energy carried by an electric current.

radiant energy (light energy)

is the energy carried by electromagnetic waves

why do we call radiant energy, light energy

because most electromagnetic waves are at wavelengths and energies our eyes cannot see

nuclear energy

is energy stored in the nucleus of an atom.

example of Gravitational potential energy

  A book on a shelf could fall to the ground.

example of Elastic potential energy

A stretched rubber band will snap back to its original shape when you release it.

example of Chemical potential energy

Food is broken down by your digestive system to provide thermal and kinetic energy

example of radiant energy (light energy)

x-rays, microwaves, ultraviolet light, and infrared light.

can radiant energy travel through empty spaces?

yes

The Law of Conservation of Energy (The First Law of Thermodynamics)

Energy can not be created nor destroyed.  It can only be transformed from one kind into another

when throwing a ball up into the air how does its energy change?

kinetic-potential-stops(all kinetic energy turns into potential)-kenetic

Law of Conservation of Energy

the total amount of energy of the ball does not change- ever

waste energy

is energy that can not be used again

Third Law of Thermodynamics

It is impossible not to waste any energy at all