Energy

Question 1

How many main stores of energy are there?

Answer 1

7

Question 2

The energy stored when repelling poles have been pushed closer together or when attracting poles have been pulled further apart is called?

Answer 2

Magnetic

Question 3

The energy of a moving object is called?

Answer 3

Kinetic

Question 4

The energy stored in the nucleus of an atom is called?

Answer 4

Nuclear

Question 5

The scientific way of saying that energy has been transferred is called?

Answer 5

Work

Question 6

When energy is transferred, not all is directly converted as intended and some of that energy is?

Answer 6

Dissipated

Dissipation is a term that is often used to describe ways in which energy is wasted.

Question 7

Any energy that is not transferred to useful energy stores is said to be wasted. Why?

Answer 7

Because energy is lost to the surroundings.

Question 8

In a mechanical system, energy is dissipated when two surfaces rub together. Work is done which causes heating of the two surfaces. This work done is called?

Answer 8

Friction

Question 9

Energy can be transferred usefully, stored or dissipated, but it cannot be?

Answer 9

Created or destroyed.

Question 10

What type of energy does a skydiver lose when he jumps out of a plane?

Answer 10

Gravitaional Potential Energy

Question 11

When a skydiver jumps out of a plane, he begins to lose gravitational potential energy as his height decreases. This energy is transferred to what type of energy as his speed increases as he falls?

Answer 11

Kinetic Energy

Question 12

The amount of kinetic energy in a moving object can be calculated using the equation?

Answer 12

Kinetic Energy=1/2 x mass x speed²

Question 13

Work is defined as?

Answer 13

The product of net forces on object and the distance the object is moved

When a force causes a body to move, work is being done on the object by the force. Work is the measure of energy transfer when a force (F) moves an object through a distance (d).

Question 14

The equation for work is?

Answer 14

Work= Force (N) x Distance (meters)

Question 15

The units of work are:

Answer 15

Joules (J)

Question 16

What is the law of conservation of energy?

Answer 16

Energy cannot be created or destroyed.

Question 17

What is the most important component when determining kinetic energy?

Answer 17

speed

Question 18

Define Kinetic Energy?

Answer 18

Energy of motion

Question 19

Define Potential Energy?

Answer 19

Energy that is stored and held in readiness

Question 20

Define energy?

Answer 20

Ability to do work

Question 21

What is the difference between potential and kinetic energy?

Answer 21

Potential is the amount of energy stored and kinetic is in amount of energy in motion

Question 22

What does potential energy depend on?

Answer 22

Mass and height

Question 23

What does kinetic energy depend on?

Answer 23

Mass and velocity

Question 24

What is power?

Answer 24

Rate at which work is done

Question 25

What is mechanical energy?

Answer 25

Sum of all energies

Question 26

The SI unit for power is called the?

Answer 26

Watt

Question 27

What is Chemical Energy?

Answer 27

The energy stored in chemical bonds

Question 28

When work is done, energy has been?

Answer 28

Transferred When work is done, energy has been transferred from one energy store to another, and so: Energy transferred = Work done Energy transferred and work done are both measured in **Joules (J).**

Question 29

The amount of work done when a force acts on a body depends on two things:

Answer 29

* The size of the force acting on the object * The distance through which the force causes the body to move in the direction of the force

Question 30

What is the Work Done:

Answer 30

A force of 10 N causes the box to move a horizontal distance of 2 m, so: W = F x D W= 10 x 2 W=20J

Question 31

When work is done on an object, energy is transferred. The rate at which this energy is transferred is called?

Answer 31

Power

Question 32

The equation used to calculate power is?

Answer 32

Power = W/T

Question 33

An electric motor is used to lift a 2 N weight through a vertical height of 10 m, in 10 seconds. What is its power?

Answer 33

Work Done =FxD (2 x 10) Power = W/T P= 20J/10s = 2W

Question 34

How good a device is at transferring energy input to useful energy output is called?

Answer 34

Efficiency.

Question 35

How is thermal energy transmitted through a conductor?

Answer 35

Easily

Question 36

What happens to the Ions when one end of a metal rod is put into a fire?

Answer 36

They vibrate faster

Question 37

How does an insulator affect the transfer of energy?

Answer 37

It tries to prevent the transfer of energy

Question 38

Applying heat to one end of a metal rod, what type of energy is occuring within the rod?

Answer 38

Conduction

Question 39

A material that heats the quickest is said to have a high thermal?

Answer 39

Conductivity.

Question 40

When materials are heated, the molecules gain which type of energy?

Answer 40

Kinetic

Question 41

The specific heat capacity of a material is the energy required to raise?

Answer 41

One kilogram (kg) of the material by one degree Celsius (°C).

Question 42

Which is the best insulator? * Copper * Tin * Wood

Answer 42

Wood

Question 43

What is a thermal conductor?

Answer 43

A material that easily allows thermal energy through

Question 44

Why is loft insulation so effective? * It traps air which helps to reduce heat lost from the home * It is itchy but reduces noise in the loft * The fibres do not burn easily if there is a fire

Answer 44

It traps air which helps to reduce heat lost from the home

Question 45

What would make the best material for wrapping around a mug to keep a hot drink warm for as long as possible? * Aluminium foil * Bubble wrap * Copper foil

Answer 45

Bubble Wrap

Question 46

What happens to the molecules in a liquid as it gets hotter? * Speed up * Slow down * Stay at the same speed

Answer 46

Speed Up

Question 47

What happens to the molecules in a solid as it gets hotter? * Start vibrating * Vibrate faster * Vibrate slower

Answer 47

Vibrate faster

Question 48

When doing an experiment to find the specific heat capacity, which of these items of equipment is not needed? * A heater * A force meter * A thermometer

Answer 48

A force meter

Question 49

If the same amount of heat energy were to be provided to a block of twice the mass of the same material, what would happen to the temperature rise? * It would be double * It would be the same * It would be half

Answer 49

It would be half The temperature rise would be half as much. If there is twice as much mass then the same energy must spread out twice as far so each particle does not gain as much energy as before.