Topic 3 - Energy

Question 1

What is energy?

Answer 1

the ability to do work or cause a change

Question 2

What is the unit for energy?

Answer 2

Joules

Question 3

What is electrical energy? eg

Answer 3

• caused by movement of charges
  charger

Question 4

What is nuclear energy? eg

Answer 4

• energy stored in nucleus of atom
• released from nuclear reactions
  nuclear power plants
  sun/stars

Question 5

What is sound energy? eg

Answer 5

• anything noisy
• type of kinetic energy
  speakers
  vocal chords

Question 6

What is heat energy? eg

Answer 6

• determines how active an objects atoms are
  fire

Question 7

What is light energy? eg

Answer 7

• anything luminous
  sun
  light bulbs
  candles

Question 8

What is chemical energy? eg

Answer 8

• potential energy stored within chemical bonds of an object
  batteries
  coal

Question 9

What is gravitational energy? eg

Answer 9

• potential energy due to an objects position (calc by m x h x g
  bird on tree brand

Question 10

What is elastic energy? eg

Answer 10

• potential due to compression or expansion of an object
  rubber band

Question 11

What is the difference between kinetic energy and potential energy?

Answer 11

kinetic energy is the energy due to its motion and potential energy is stored energy

Question 12

What are the 3 types of potential energy?

Answer 12

chemical
elastic
gravitational

Question 13

What is the g always when calculating GPE?

Answer 13

10

Question 14

What is meant by the term work?

Answer 14

the transfer of energy by a force acting on an object as it is displaced

Question 15

What is the conservation of energy law?

Answer 15

• energy cannot be created or destroyed
• when energy is converted from one form to another, total energy stays the same

Question 16

What is an energy transfer?

Answer 16

• energy is passed along but the type of energy is not changed

Question 17

What is an energy transformation?

Answer 17

• energy changes from one type of energy to another

Question 18

eg energy transfer

Answer 18

kickicking a soccer ball w/ kinetic energy from leg -> ball moving with kinetic energy

Question 19

eg energy transformation

Answer 19

light with electrical energy -> heat + light

Question 20

Energy flow diagram for girl eating apple then running to bus

Answer 20

chemical potential -> kinetic + heat

Question 21

What is thermodynamics?

Answer 21

study of how heat can be transferred between objects or transformed into other forms of energy

Question 22

What is a closed thermodynamic system?

Answer 22

a type of thermodynamic system that can exchange heat with its surroundings but mass cannot be exchanged

Question 23

How does thermal equilibrium occur?

Answer 23

when 2 objects are at different temperatures and there is a temp gradient
- when the thermal energy of an object is the same as its surroundings, thermal equilibrium is reached

Question 24

How does conduction work as an example of heat transfer?

Answer 24

• conduction occurs when two objects at different temps come in contact with each other
• heat flows from the warmer to cooler obejct until they are both at the same temp

Question 25

How does convection work as an example of heat transfer?

Answer 25

• transfer of heat by the movement of a fluid (liquid or gas) between areas of dif temp
• warm air is less