Speed is the distance travelled by an object every second .

Why is a trundle wheel more suitable than a metre rule for measuring long distances?

A trundle wheel is more suitable for measuring long distances because a metre rule is too short and impractical to use repeatedly over large distances. A trundle wheel counts rotations to give an accurate total length.

True or False? A light gate measures the distance an object travels directly.

False. A light gate measures time , not distance directly. The distance is determined separately, for example by measuring the length of the flag attached to the moving object.

To calculate speed, you must measure the .......... travelled and the .......... taken.

To calculate speed, you must measure the distance travelled and the time taken.

When using a single light gate , what measurement provides the distance travelled?

When using a single light gate, the distance travelled is given by the length of the flag that passes through the gate.

What is a light gate ?

A light gate is a piece of digital equipment used to measure time more accurately than a stopwatch, by detecting when an object passes through a beam of light.

True or False? A metre rule is the most appropriate tool for measuring the length of an athletics track.

False. A metre rule is too short to be practical for measuring long distances. A more appropriate tool would be a tape measure or a trundle wheel .

When using two light gates to measure speed, what is the role of each gate?

When using two light gates, the first gate starts the timer when the object passes through it, and the second gate stops the timer.

As the flag passes through a light gate, it .......... a beam of light and .......... a timer.

As the flag passes through a light gate, it blocks a beam of light and starts a timer.

Speed is the distance an object travels per unit time , calculated using: speed = distance ÷ time.

For an object moving at constant speed, speed equals .......... divided by .......... .

For an object moving at constant speed, speed equals distance divided by time .

Florence Griffith Joyner ran 100 m in 10.49 s. Calculate her average speed .

Florence Griffith Joyner's average speed is calculated using: average speed = total distance ÷ time taken. average speed = 100 ÷ 10.49 average speed = 9.53 m/s (3 s.f.)

True or False? The average speed of an object equals its speed at every moment during a journey.

False. Average speed is total distance divided by total time. During a journey with non-uniform motion , the object's speed at any given moment may be higher or lower than the average.

What is non-uniform motion ?

Non-uniform motion is motion in which an object's speed , direction or both are changing throughout the journey.

Why do we use average speed rather than a single speed value for objects with non-uniform motion?

We use average speed for objects with non-uniform motion because their speed is not constant — it changes throughout the journey. Average speed gives a useful single value based on total distance and total time .

True or False? Average speed is calculated using total distance and total time taken.

True. Average speed = total distance ÷ total time. This equation is used when an object is not moving at a constant speed, i.e. it has non-uniform motion .

When an object's speed changes during a journey, it is said to have .......... motion.

When an object's speed changes during a journey, it is said to have non-uniform motion.

A car travels at an average speed of 15 m/s for 20 s. What distance does it cover?

The distance covered is calculated using: distance = average speed × time. distance = 15 × 20 distance = 300 m

What are SI base units ?

SI base units are the seven fundamental units from which all other physical units are derived .

Complete the table of common SI prefixes. Prefix Symbol Multiplier kilo 10 3 M 10 6 milli 10 -3 n 10 -9

Prefix Symbol Multiplier kilo k 10 3 mega M 10 6 milli m 10 -3 nano n 10 -9

What is the SI base unit of mass and its symbol?

The SI base unit of mass is the kilogram , symbol kg .

True or False? The SI base unit of length is the centimetre (cm).

False. The SI base unit of length is the metre (m). The centimetre is a sub-multiple of the metre, where 1 cm = 10 -2 m.

What does the prefix kilo mean?

The prefix kilo (symbol k) means multiplied by 10 3 (one thousand).

Convert 5 km into metres.

5 km converted to metres: 5 km = 5 × 10 3 m = 5000 m

True or False? A millisecond (ms) is equal to 10 -3 seconds.

True. The prefix milli means 10 -3 , so 1 ms = 10 -3 s. There are 1000 milliseconds in one second.

The prefix nano has the symbol .......... and represents 10 -9 (one billionth).

The prefix nano has the symbol n and represents 10 -9 (one billionth).

What is the SI base unit of electric current and its symbol?

The SI base unit of electric current is the ampere , symbol A .

What is a scalar quantity?

A scalar quantity is a physical quantity that has magnitude only, with no direction.

Give two examples of scalar quantities from everyday physics.

Two examples of scalar quantities are: Mass : has magnitude but no direction Distance : describes how far an object travels, with no direction stated

True or False? Velocity is a scalar quantity because it describes how fast an object moves.

False. Velocity is a vector quantity because it describes both the speed of an object and the direction in which it is travelling.

A scalar quantity has .......... only, while a vector quantity has both magnitude and .......... .

A scalar quantity has magnitude only, while a vector quantity has both magnitude and direction .

What is a vector quantity?

A vector quantity is a physical quantity that has both magnitude and direction .

An athlete runs 300 m around a track and finishes 100 m from their starting point. What is the difference between their distance and displacement ?

The athlete's distance is 300 m, the total length of the path they ran. Their displacement is 100 m in a specific direction from their starting point. Distance is scalar. Displacement is a vector.

True or False? Both distance and displacement are scalar quantities.

False. Distance is a scalar quantity (magnitude only). Displacement is a vector quantity because it describes both how far an object is from its starting position and the direction .

What does a negative sign indicate when describing a vector quantity?

A negative sign indicates the direction of the vector quantity is opposite to the defined positive direction. For example, a velocity of −60 km/h means the object travels in the opposite direction to a velocity of +60 km/h.

Displacement is a .......... quantity because it describes both how far an object is from its starting point and its .......... .

Displacement is a vector quantity because it describes both how far an object is from its starting point and its direction .

What is displacement ?

Displacement is the distance from an object's starting position in a specific direction . It is a vector quantity.

What is a distance-time graph ?

A distance-time graph shows how the distance of an object from a starting position changes over time.

What does the gradient of a distance-time graph represent?

The gradient of a distance-time graph represents the speed of the object. A steeper gradient means a greater speed.

True or False? A curved line on a distance-time graph means the object is moving at a constant speed.

False. A curved line means the object is moving at a changing speed . A straight line represents constant speed.

On a distance-time graph, a flat horizontal line means the object is ..........

On a distance-time graph, a flat horizontal line means the object is stationary .

On a distance-time graph, what does a steeper slope tell you compared with a shallower slope?

A steeper slope means the object is moving at a greater speed than an object with a shallower slope.

What is a velocity-time graph ?

A velocity-time graph shows how the velocity of a moving object changes over time.

True or False? A flat horizontal line on a velocity-time graph means the object has zero acceleration.

True. A flat line on a velocity-time graph means the object is moving at a constant velocity , so its acceleration is zero.

The table below describes the shape of a line on a velocity-time graph. Complete the missing descriptions. Shape of line What it tells you Straight line with positive slope Flat horizontal line Straight line with negative slope

The table below describes the shape of a line on a velocity-time graph. Complete the missing descriptions. Shape of line What it tells you Straight line with positive slope Constant acceleration Flat horizontal line Constant velocity (zero acceleration) Straight line with negative slope Constant deceleration

How do you calculate the acceleration of an object from a velocity-time graph?

You calculate the acceleration from the gradient of the line on a velocity-time graph. Draw a large gradient triangle and divide the change in velocity by the change in time.

What does the area under a velocity-time graph represent? (Higher Tier Only)

The area under a velocity-time graph represents the displacement (or distance travelled) by the object.

What shape does the area under a velocity-time graph form when the object moves at constant velocity ? (Higher Tier Only)

When the object moves at constant velocity , the area under the graph forms a rectangle .

True or False? The area under a velocity-time graph for an object accelerating uniformly from rest forms a triangle. (Higher Tier Only)

True. When an object accelerates uniformly from rest, the area under the velocity-time graph forms a triangle .

For a triangle on a velocity-time graph, the distance travelled = ½ × .......... × .......... . (Higher Tier Only)

(Higher Tier Only) For a triangle on a velocity-time graph, the distance travelled = ½ × base × height .

A velocity-time graph shows a section where the object decelerates from 20 m/s to 0 m/s over 10 s. What is the distance travelled in this section? (Higher Tier Only)

The area under the graph forms a triangle . Distance = ½ × base × height = ½ × 10 × 20 = 100 m .

GCSEPhysicsOCRPhysics A (Gateway)Flashcards2. ForcesMotion

Motion (OCR GCSE Physics A (Gateway)): Flashcards

Exam code: J249

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FrontMeasuring Speed
What is speed?

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Cards in this collection (63)

What is speed?
Speed is the distance travelled by an object every second.
Why is a trundle wheel more suitable than a metre rule for measuring long distances?
A trundle wheel is more suitable for measuring long distances because a metre rule is too short and impractical to use repeatedly over large distances. A trundle wheel counts rotations to give an accurate total length.
True or False?
A light gate measures the distance an object travels directly.
False.
A light gate measures time, not distance directly. The distance is determined separately, for example by measuring the length of the flag attached to the moving object.
To calculate speed, you must measure the .......... travelled and the .......... taken.
To calculate speed, you must measure the distance travelled and the time taken.
When using a single light gate, what measurement provides the distance travelled?
When using a single light gate, the distance travelled is given by the length of the flag that passes through the gate.
What is a light gate?
A light gate is a piece of digital equipment used to measure time more accurately than a stopwatch, by detecting when an object passes through a beam of light.
True or False?
A metre rule is the most appropriate tool for measuring the length of an athletics track.
False.
A metre rule is too short to be practical for measuring long distances. A more appropriate tool would be a tape measure or a trundle wheel.
When using two light gates to measure speed, what is the role of each gate?
When using two light gates, the first gate starts the timer when the object passes through it, and the second gate stops the timer.
As the flag passes through a light gate, it .......... a beam of light and .......... a timer.
As the flag passes through a light gate, it blocks a beam of light and starts a timer.
What is speed?
Speed is the distance an object travels per unit time, calculated using: speed = distance ÷ time.
For an object moving at constant speed, speed equals .......... divided by ...........
For an object moving at constant speed, speed equals distance divided by time.
Florence Griffith Joyner ran 100 m in 10.49 s. Calculate her average speed.
Florence Griffith Joyner's average speed is calculated using: average speed = total distance ÷ time taken.
average speed = 100 ÷ 10.49
average speed = 9.53 m/s (3 s.f.)
True or False?
The average speed of an object equals its speed at every moment during a journey.
False.
Average speed is total distance divided by total time. During a journey with non-uniform motion, the object's speed at any given moment may be higher or lower than the average.
What is non-uniform motion?
Non-uniform motion is motion in which an object's speed, direction or both are changing throughout the journey.
Why do we use average speed rather than a single speed value for objects with non-uniform motion?
We use average speed for objects with non-uniform motion because their speed is not constant — it changes throughout the journey. Average speed gives a useful single value based on total distance and total time.
True or False?
Average speed is calculated using total distance and total time taken.
True.
Average speed = total distance ÷ total time. This equation is used when an object is not moving at a constant speed, i.e. it has non-uniform motion.
When an object's speed changes during a journey, it is said to have .......... motion.
When an object's speed changes during a journey, it is said to have non-uniform motion.
A car travels at an average speed of 15 m/s for 20 s. What distance does it cover?
The distance covered is calculated using: distance = average speed × time.
distance = 15 × 20
distance = 300 m
What are SI base units?
SI base units are the seven fundamental units from which all other physical units are derived.
Complete the table of common SI prefixes.
Prefix
Symbol
Multiplier
kilo
10³
M
10⁶
milli
10^-3
n
10^-9
Prefix
Symbol
Multiplier
kilo
k
10³
mega
M
10⁶
milli
m
10^-3
nano
n
10^-9
What is the SI base unit of mass and its symbol?
The SI base unit of mass is the kilogram, symbol kg.
True or False?
The SI base unit of length is the centimetre (cm).
False.
The SI base unit of length is the metre (m). The centimetre is a sub-multiple of the metre, where 1 cm = 10^-2 m.
What does the prefix kilo mean?
The prefix kilo (symbol k) means multiplied by 10³ (one thousand).
Convert 5 km into metres.
5 km converted to metres:
5 km = 5 × 10³ m = 5000 m
True or False?
A millisecond (ms) is equal to 10^-3 seconds.
True.
The prefix milli means 10^-3, so 1 ms = 10^-3 s. There are 1000 milliseconds in one second.
The prefix nano has the symbol .......... and represents 10^-9 (one billionth).
The prefix nano has the symbol n and represents 10^-9 (one billionth).
What is the SI base unit of electric current and its symbol?
The SI base unit of electric current is the ampere, symbol A.
What is a scalar quantity?
A scalar quantity is a physical quantity that has magnitude only, with no direction.
Give two examples of scalar quantities from everyday physics.
Two examples of scalar quantities are:
1. Mass: has magnitude but no direction
2. Distance: describes how far an object travels, with no direction stated
True or False?
Velocity is a scalar quantity because it describes how fast an object moves.
False.
Velocity is a vector quantity because it describes both the speed of an object and the direction in which it is travelling.
A scalar quantity has .......... only, while a vector quantity has both magnitude and ...........
A scalar quantity has magnitude only, while a vector quantity has both magnitude and direction.
What is a vector quantity?
A vector quantity is a physical quantity that has both magnitude and direction.
An athlete runs 300 m around a track and finishes 100 m from their starting point. What is the difference between their distance and displacement?
The athlete's distance is 300 m, the total length of the path they ran. Their displacement is 100 m in a specific direction from their starting point. Distance is scalar. Displacement is a vector.
True or False?
Both distance and displacement are scalar quantities.
False.
Distance is a scalar quantity (magnitude only). Displacement is a vector quantity because it describes both how far an object is from its starting position and the direction.
What does a negative sign indicate when describing a vector quantity?
A negative sign indicates the direction of the vector quantity is opposite to the defined positive direction. For example, a velocity of −60 km/h means the object travels in the opposite direction to a velocity of +60 km/h.
Displacement is a .......... quantity because it describes both how far an object is from its starting point and its ...........
Displacement is a vector quantity because it describes both how far an object is from its starting point and its direction.
What is displacement?
Displacement is the distance from an object's starting position in a specific direction. It is a vector quantity.
What is a distance-time graph?
A distance-time graph shows how the distance of an object from a starting position changes over time.
What does the gradient of a distance-time graph represent?
The gradient of a distance-time graph represents the speed of the object. A steeper gradient means a greater speed.
True or False?
A curved line on a distance-time graph means the object is moving at a constant speed.
False.
A curved line means the object is moving at a changing speed. A straight line represents constant speed.
On a distance-time graph, a flat horizontal line means the object is ..........
On a distance-time graph, a flat horizontal line means the object is stationary.
On a distance-time graph, what does a steeper slope tell you compared with a shallower slope?
A steeper slope means the object is moving at a greater speed than an object with a shallower slope.
What is a velocity-time graph?
A velocity-time graph shows how the velocity of a moving object changes over time.
True or False?
A flat horizontal line on a velocity-time graph means the object has zero acceleration.
True.
A flat line on a velocity-time graph means the object is moving at a constant velocity, so its acceleration is zero.
The table below describes the shape of a line on a velocity-time graph. Complete the missing descriptions.
Shape of line
What it tells you
Straight line with positive slope
Flat horizontal line
Straight line with negative slope
The table below describes the shape of a line on a velocity-time graph. Complete the missing descriptions.
Shape of line
What it tells you
Straight line with positive slope
Constant acceleration
Flat horizontal line
Constant velocity (zero acceleration)
Straight line with negative slope
Constant deceleration
How do you calculate the acceleration of an object from a velocity-time graph?
You calculate the acceleration from the gradient of the line on a velocity-time graph. Draw a large gradient triangle and divide the change in velocity by the change in time.
What does the area under a velocity-time graph represent? (Higher Tier Only)
The area under a velocity-time graph represents the displacement (or distance travelled) by the object.
What shape does the area under a velocity-time graph form when the object moves at constant velocity? (Higher Tier Only)
When the object moves at constant velocity, the area under the graph forms a rectangle.
True or False?
The area under a velocity-time graph for an object accelerating uniformly from rest forms a triangle. (Higher Tier Only)
True.
When an object accelerates uniformly from rest, the area under the velocity-time graph forms a triangle.
For a triangle on a velocity-time graph, the distance travelled = ½ × .......... × ........... (Higher Tier Only)
(Higher Tier Only)
For a triangle on a velocity-time graph, the distance travelled = ½ × base × height.
A velocity-time graph shows a section where the object decelerates from 20 m/s to 0 m/s over 10 s. What is the distance travelled in this section? (Higher Tier Only)
The area under the graph forms a triangle. Distance = ½ × base × height = ½ × 10 × 20 = 100 m.
The table below shows two shapes that can appear under a velocity-time graph. Complete the formula for the area of each. (Higher Tier Only)
Shape
Situation
Area formula
Rectangle
Constant velocity
Triangle
Uniform acceleration from rest, or deceleration to rest
(Higher Tier Only)
The table below shows two shapes that can appear under a velocity-time graph. Complete the formula for the area of each.
Shape
Situation
Area formula
Rectangle
Constant velocity
Base × height
Triangle
Uniform acceleration from rest, or deceleration to rest
½ × base × height
True or False?
To find the total distance on a velocity-time graph with multiple sections, you only need to calculate the area of the largest section. (Higher Tier Only)
False.
You must calculate the area of each enclosed section separately and then add them together to find the total distance travelled.
A velocity-time graph shows a rectangle of base 30 s and height 17.5 m/s. What is the distance covered in this section? (Higher Tier Only)
The area is a rectangle, so distance = base × height = 30 × 17.5 = 525 m.
What is acceleration?
Acceleration is the rate of change of velocity — how much an object's velocity changes every second. It is measured in metres per second squared (m/s²).
The equation for acceleration is: acceleration = .......... ÷ ...........
The equation for acceleration is: acceleration = change in velocity ÷ time taken.
True or False?
A negative value for acceleration always means the object is stationary.
False.
A negative acceleration means the object is slowing down (decelerating), not that it is stationary. The object is still moving but its speed is decreasing.
How do you calculate the change in velocity of an object?
Change in velocity = final velocity − initial velocity. If the result is negative, the object is slowing down.
What is deceleration?
Deceleration is a negative acceleration — it describes an object that is slowing down. The value of acceleration is negative when an object decelerates.
A car slows from 20 m/s to 8 m/s in 6 s. What is its acceleration?
Change in velocity = 8 − 20 = −12 m/s.
Acceleration = −12 ÷ 6 = −2 m/s².
The negative sign shows the car is decelerating.
True or False?
The equation v² − u² = 2 × a × x can be used when the time taken is not known. (Higher Tier Only)
True.
The uniform acceleration equation v² − u² = 2 × a × x is used when time is not given, allowing calculation of final speed, initial speed, acceleration, or distance.
The table below lists the quantities in the uniform acceleration equation. Complete the units column. (Higher Tier Only)
Symbol
Quantity
Unit
v
final speed
u
initial speed
a
acceleration
x
distance travelled
The table below lists the quantities in the uniform acceleration equation. Complete the units column.
Symbol
Quantity
Unit
v
final speed
m/s
u
initial speed
m/s
a
acceleration
m/s²
x
distance travelled
m
A car starts from rest and reaches 16 m/s with an acceleration of 2.5 m/s². What distance does it travel? (Higher Tier Only)
Using v² − u² = 2 × a × x:
16² − 0² = 2 × 2.5 × x
256 = 5x
x = 51.2 m

Prefix	Symbol	Multiplier
kilo		10³
	M	10⁶
milli		10^-3
	n	10^-9

Prefix	Symbol	Multiplier
kilo	k	10³
mega	M	10⁶
milli	m	10^-3
nano	n	10^-9

Shape of line	What it tells you
Straight line with positive slope
Flat horizontal line
Straight line with negative slope

Shape of line	What it tells you
Straight line with positive slope	Constant acceleration
Flat horizontal line	Constant velocity (zero acceleration)
Straight line with negative slope	Constant deceleration

Shape	Situation	Area formula
Rectangle	Constant velocity
Triangle	Uniform acceleration from rest, or deceleration to rest

Shape	Situation	Area formula
Rectangle	Constant velocity	Base × height
Triangle	Uniform acceleration from rest, or deceleration to rest	½ × base × height

Symbol	Quantity	Unit
v	final speed
u	initial speed
a	acceleration
x	distance travelled

Symbol	Quantity	Unit
v	final speed	m/s
u	initial speed	m/s
a	acceleration	m/s²
x	distance travelled	m

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