SCIENCE EXAM

Question 1

Distance

Answer 1

A measure of how far apart objects are e.g. metres, kilometres

Question 2

Speed

Answer 2

A measure of how fast something moves

Question 3

Average Speed

Answer 3

How fast something moves overall

Question 4

Instantaneous speed

Answer 4

Your speed at a particular time

Question 5

Acceleration

Answer 5

Rate at which the object changes it’s velocity

Question 6

Terminal Velocity

Answer 6

The constant speed that a free falling object eventually reaches when the resistance of the medium (i.e. Air Resistance) through which it is falling prevents further acceleration

Question 7

Average acceleration formula

Answer 7

Change in speed/time
=final speed-initial speed/time
or v-u/t

Question 8

Final speed formula

Answer 8

Final speed=Initial speed+(average acceleration x time taken)
or v=u+a x t

Question 9

Converting units

Answer 9

Speed in km/h divide 3.6 to get m/s
Speed in m/s multiply 3.6 to get km/h

Question 10

Average speed formula

Answer 10

Average Speed=Distance travelled/time taken
or v=d/t

Question 11

Distance Formula

Answer 11

Distance=Average speed x time
or d=v x t

Question 12

Time formula

Answer 12

Time=Distance/average speed
or t=d/v

Question 13

Distance time graph

Answer 13

Shows how far an object travels as time progresses

Question 14

Features of a Distance time graph

Answer 14

1.Flat line
2.Steep slope
3.Gentle slope
4.Slope

Question 15

Flat line

Answer 15

Indicates that motion has stopped

Question 16

Steep slope

Answer 16

indicates that object covers greater distance, means it’s moving fast

Question 17

Gentle slope

Answer 17

Means moving slow

Question 18

Slope

Answer 18

Is also known as gradient. The gradient or slope is equivalent to the objects speed over a time interval

Question 19

Speed time graphs

Answer 19

Shows an objects speed changes over time

Question 20

Features of a speed time graph

Answer 20

-Constant, flat line
-Increase, graph rising upwards
-Decrease, graph falling down

Question 21

Newton’s First Law

Answer 21

An object at rest will remain this way unless it is acted upon by a force. Basically an object will ‘keep doing what it was doing’ unless acted on by an unbalanced force.

Question 22

Inertia

Answer 22

The tendency to resist any change in motion. The larger that mass of an object, the greater the it’s inertia, and the harder it is to change its motion.

Question 23

Unbalanced forces

Answer 23

Causes change in speed, direction, state or motion.

Question 24

Balanced forces

Answer 24

If the forces of objects are equal and opposite, they are said to be balanced, and the object experiences no change in motion.

Question 25

Newtons second law

Answer 25

An object will accelerate in the direction of an unbalanced force acting upon it. The size of this acceleration depends upon the mass of the object and the size of the force acting on it.

Question 26

According to Newton’s second law

Answer 26

A larger force is needed to accelerate a heavy load then a lighter load. A larger force is required to make something accelerate at a faster rate.

Question 27

Calculating force/mass/acceleration

Answer 27

By using the formula F=ma

Question 28

Newton’s third law

Answer 28

For every action there is an equal and opposite reaction force

Question 29

According to newton’s third law

Answer 29

The acceleration that an object experiences due to a force depends upon its mass. That means an object with low mass will travel with much greater acceleration than a more massive object.

Question 30

Kinetic energy

Answer 30

The energy of a moving object is called kinetic energy. The amount of kinetic energy and object has depends on its mass and speed

Question 31

Potential Energy

Answer 31

Potential energy is the energy that an object has because of its position or structure. Also called stored energy. Gives the objects the capacity to make things happen.

Question 32

Elastic Potential Energy

Answer 32

The stretched or compressed spring has elastic potential energy. The energy is converted into kinetic energy when the spring is released and returns to its original shape.

Question 33

Law of Conservation of energy

Answer 33

Energy may be transferred from an object to matter, but it is never destroyed or created.

Question 34

Energy transfer and transformation

Answer 34

-Car crashes -Pendulum -Lifting -Dropping

Question 35

Energy efficiency

Answer 35

A little energy is usually ‘lost’ because it changes into non-useful forms such as heat and sounds

Question 36

Energy Calculations-Kinetic Energy

Answer 36

Kinetic energy=1/2mass x speed* or Ek=1/2mv*2

Question 37

Energy Potential Energy-Gravitational Potential Energy

Answer 37

GPE (Gravitational Potential energy)=Mass x acceleration due to gravity x height or Ep=mgh

Question 38

Energy flow diagram

Answer 38

Electrical energy->kinetic energy+sound energy+heat energy

Question 39

Efficiency transfer formula

Answer 39

efficiency=useful energy output/total energy input x 100%

Question 40

Car crashes

Answer 40

Example: A car moving at 100km/h hits a concrete wall -Moving car : Kinetic Energy -Metal Deformation : Heat energy -Noise : Sound energy -Springiness in the car structures : Elastic Potential Energy

Question 41

Green house effect