CP1

Question 1

What is a vector quantity?

Answer 1

A quantity that have both magnitude and direction.

Question 2

What is a scalar quantity?

Answer 2

A quantity that has magnitude but no direction.

Question 3

What is magnitude?

Answer 3

The size of something, such as the size of a force or the measurement of a distance.

Question 4

What direction does the force of weight act towards?

Answer 4

It acts towards the centre of the earth.

Question 5

What is displacement and is it a scalar or a vector?

Answer 5

The distance covered in a straight in line a particular direction (e.g. 300m north) and it is a vector.

Question 6

What are some examples of scalar quantities?

Answer 6

1. Mass
2. Speed
3. Distance
4. Energy

Question 7

What are some examples of vector quantities?

Answer 7

1. Force
2. Weight
3. Acceleration
4. Displacement

Question 8

What is velocity and is it a scalar or a vector?

Answer 8

Velocity is the speed of an object in a particular direction (e.g. 20m/s northwards) and it is a vector.

Question 9

What is the difference between distance and displacement?

Answer 9

Distance is the measure of how far an object travels whereas Displacement is how far an object has travelled in a particular direction.

Question 10

What is the difference between speed and velocity?

Answer 10

Speed is the measure of the distance an object travels in a given time whereas Velocity is the speed of an object in a particular direction.

Question 11

What is acceleration?

Answer 11

A measure of how fast the velocity of an object is changing.

Question 12

What is momentum?

Answer 12

A combination of mass and velocity.

Question 13

What is the formula triangle for Speed, Distance and Time?

Answer 13

Distance
Speed | Time

Question 14

What is the formula to find the average speed?

Answer 14

Average Speed (m/s) = Distance(m)/Time(s)

Question 15

What are some common units for speed?

Answer 15

m/s, km/h, mph

Question 16

What is instantaneous speed?

Answer 16

The speed at a particular point in a journey.

Question 17

What is the difference between instantaneous speed and average speed?

Answer 17

Average speed is the speed across the whole journey while instantaneous speed is the speed at a particular point in a journey.

Question 18

How do you measure the speed of high-speed objects?

Answer 18

By using lightgates.

Question 19

What are light gates?

Answer 19

A piece of apparatus containing an infrared beam that is transmitted from a source onto a detector, which can accurately read the speeds of high-speed objects.

Question 20

Why are light gates used to measure speed of high-speed objects instead of a stopwatch?

Answer 20

As they do not need the error of human reaction time to press the button on the stop watch due to infrared signals immediately being emitted once the object crosses the light gate.

Question 21

What are some typical speeds in m/s for: Airliners, Cyclists and Walking Humans?

Answer 21

Airliners: 250 m/s
Cyclists: 6 m/s
Walking Humans: 1.4 m/s

Question 22

What is the speed of sound in m/s?

Answer 22

343 m/s.

Question 23

What does a horizontal line mean in a distance/time graph?

Answer 23

It means that the object is stationary (its distance from the starting point has not changed).

Question 24

What does a straight, sloping line mean in a distance/time graph?

Answer 24

It means that the object is travelling at a constant speed.

Question 25

What does it mean when the line gets steeper in a distance/time graph?

Answer 25

It means that the speed of object is increasing.

Question 26

How is speed calculated from a distance/time graph?

Answer 26

It is calculated by finding out the gradient of the line.

Question 27

How do you calculated the gradient of a line

Answer 27

Vertical difference between two points in a graph/Horizontal difference between the same two points (rise/run)

Question 28

What is the equation for acceleration?

Answer 28

Acceleration(m/sˆ2)=change in velocity(m/s)/time taken (s) (a=v-u/t)

Question 29

What is the formula triangle for acceleration

Answer 29

V-U
A | T

Question 30

What do ‘V’ and ‘U’ stand for in the acceleration?

Answer 30

V=Final velocity
U=Initial velocity

Question 31

What is deceleration?

Answer 31

When an object is slowing down. It is a negative acceleration.

Question 32

What is the formula for deceleration?

Answer 32

final velocityˆ2 - initial velocityˆ2 = 2 x acceleration x distance ((vˆ2)- (uˆ2) = 2 x a x d)

Question 33

What is the rate of acceleration due to freefall (when only the force of gravity is acting on an object)?

Answer 33

9.8m/s which is often rounded to 10m/s in calculations.

Question 34

What does a horizontal line mean in a velocity/time graph?

Answer 34

The object is travelling at a constant velocity.

Question 35

What does a sloping line mean in a velocity/time graph?

Answer 35

The object is accelerating.

Question 36

What does a sloping line with an increasing gradient mean in a velocity/time graph?

Answer 36

The steeper the line, the greater the acceleration.

Question 37

What does a line sloping downwards mean in a velocity/time graph?

Answer 37

The object is decelerating (slowing down).

Question 38

What does a negative velocity mean in a velocity/time graph?

Answer 38

The object is moving in the opposite direction to the original velocity (e.g. if an object was moving forward in a positive velocity, it would move backwards in a negative velocity)

Question 39

How do you find the acceleration in a velocity/time graph?

Answer 39

You work out the gradient of a line (rise/run)

Question 40

How do you find the distance in a velocity/time graph?

Answer 40

By finding the area of a shape in the velocity/time graph.

Question 41

How do you find the total distance in a velocity/time graph?

Answer 41

By finding the area of all shapes in the velocity/time graph and adding them all together.

Question 42

Why does the area under part of a velocity/time graph give you the distance covered?

Answer 42

As displacement is velocity x change in time.