Speed is the distance travelled per unit time .

True or False? Speed is a vector quantity.

False. Speed is a scalar quantity because it only contains magnitude.

Define average speed .

Average speed is the total distance travelled divided by the total time taken.

What does velocity describe that speed does not?

Velocity describes both magnitude and direction of motion whereas speed describes only magnitude.

Velocity is defined as the rate of change of displacement with respect to time.

True or False? Velocity is a scalar quantity.

False. Velocity is a vector quantity because it includes direction .

What units are used to measure speed and velocity?

Both speed and velocity are measured in metres per second (m/s).

What is the significance of negative velocity values?

The significance of negative velocity values indicates motion in the opposite direction.

How is displacement different from distance in calculating velocity?

Displacement is different from distance in calculating velocity because it accounts for direction.

What is the difference between speed and velocity?

The difference between speed and velocity is that speed is a scalar , while velocity is a vector as it includes direction.

How do you calculate the total distance from the average speed?

The total distance is calculated from the average speed by multiplying the average speed by the total time taken.

What is acceleration ? (Extended Tier Only)

Acceleration is the rate of change of velocity .

True or False? Acceleration measures the rate of change of velocity. (Extended Tier Only)

True. Acceleration measures the rate of change of velocity .

What units are used to measure acceleration ? (Extended Tier Only)

Acceleration is measured in metres per second squared (m/s²).

How can you find the change in velocity? (Extended Tier Only)

You can find the change in velocity by obtaining the difference between final and initial velocity.

What does a positive acceleration indicate? (Extended Tier Only)

A positive acceleration indicates that the object is speeding up .

Define acceleration . (Extended Tier Only)

Acceleration is the change in an object's velocity over time.

What does a negative acceleration indicate? (Extended Tier Only)

Negative acceleration indicates that the object is slowing down .

Define deceleration . (Extended Tier Only)

Deceleration is negative acceleration , it shows an object is slowing down.

What is the acceleration of an object with constant velocity ? (Extended Tier Only)

The acceleration of an object with constant velocity is zero .

How do you calculate acceleration from a velocity-time graph? (Extended Tier Only)

Acceleration is calculated as the gradient of a velocity-time graph.

How is direction represented in a numerical value for acceleration? (Extended Tier Only)

The direction of acceleration is represented by a positive or negative value.

How is constant speed represented on a distance-time graph?

On a distance time graph, constant speed is represented by a straight line : a steeper slope shows a greater constant speed a shallower slope shows a lower constant speed a flat, horizontal line shows a constant speed of zero

How is changing speed represented on a distance-time graph?

On a distance-time graph, changing speed is represented by a curved line .

What does a speed-time graph show?

A speed-time graph shows how the speed of a moving object varies with time .

What is constant acceleration on a speed-time graph?

Constant acceleration on a speed-time graph is represented by a straight , sloping line .

True or False? A gentle slope on a speed-time graph represents large acceleration.

False. A gentle slope on a speed-time graph represents a small acceleration.

What does a flat , horizontal line represent on a speed-time graph?

A flat, horizontal line indicates that the acceleration is zero , meaning the object is moving at a constant speed.

What does the area under a speed-time graph represent?

The area under a speed-time graph represents the distance travelled by the object.

How do you calculate the total area under a speed-time graph?

The total area under a speed-time graph shows the total distance travelled. The total area is the sum of the areas of each enclosed section (triangle or rectangle).

What shape does the area beneath a speed-time graph form for an object with constant speed ?

The area under a speed-time graph forms a rectangle .

True or False? A flat line on a speed-time graph indicates constant acceleration.

False. A flat line on a speed-time graph indicates constant speed .

True or False? All objects fall with the same acceleration in the presence of air resistance.

False. In the presence of air resistance different objects fall at different accelerations and not at g. In most Physics questions we assume that air resistance is negligible.

What is the value of the constant acceleration of free fall?

The value of the acceleration of free fall is g = 9.81m/s 2

True or False? Acceleration of free fall remains constant regardless of an object's mass.

True. Acceleration of free fall remains constant regardless of an object's mass.

Define terminal velocity . (Extended Tier Only)

Terminal velocity is the constant speed reached by a falling object when the upward force of drag equals the downward force of weight, resulting in zero acceleration .

Define air resistance .

Air resistance is the frictional force exerted by air particles on objects moving through air, which opposes the direction of motion.

How does air resistance affect the motion of falling objects? (Extended Tier Only)

Air resistance opposes the motion of objects falling through air, exerting an upward force that increases with the object's speed.

True or False? Air resistance decreases as the speed of a falling object increases. (Extended Tier Only)

False. Air resistance increases as the speed of a falling object increases.

What is the relationship between the forces of weight and air resistance during free fall? (Extended Tier Only)

During free fall, weight acts downwards while air resistance acts upwards. As the speed of the object increases, air resistance increases until it equals the weight and terminal velocity is reached.

How does terminal velocity affect the acceleration of a falling object? (Extended Tier Only)

Terminal velocity occurs when the acceleration of a falling object becomes zero because the upward drag force equals the downward force of weight, resulting in a constant speed .

True or False? Air resistance remains constant during the fall of a skydiver. (Extended Tier Only)

False. The air resistance changes with speed during the fall of a skydiver.

What factors affect the acceleration of freefall? (Extended Tier Only)

The acceleration of free fall is affected by the gravitational field strength . It is independent of the mass of the falling object.

Weight is the gravitational force exerted on an object with mass.

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Motion (Cambridge (CIE) IGCSE Physics)

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Cards in this collection (58)

What is speed?
Speed is the distance travelled per unit time.
True or False?
Speed is a vector quantity.
False.
Speed is a scalar quantity because it only contains magnitude.
Define average speed.
Average speed is the total distance travelled divided by the total time taken.
State the equation for calculating average speed.
The equation for calculating average speed is $Average speed = \frac{distance travelled}{time taken}$
What does velocity describe that speed does not?
Velocity describes both magnitude and direction of motion whereas speed describes only magnitude.
Define velocity.
Velocity is defined as the rate of change of displacement with respect to time.
What is the equation for calculating velocity?
The equation for velocity is $v = \frac{s}{t}$
Where:
- $v$ = velocity, measured in metres per second (m/s)
- $s$ = displacement, measured in metres (m)
- $t$ = time, measured in seconds (s)
True or False?
Velocity is a scalar quantity.
False.
Velocity is a vector quantity because it includes direction.
What units are used to measure speed and velocity?
Both speed and velocity are measured in metres per second (m/s).
What is the significance of negative velocity values?
The significance of negative velocity values indicates motion in the opposite direction.
How is displacement different from distance in calculating velocity?
Displacement is different from distance in calculating velocity because it accounts for direction.
What is the difference between speed and velocity?
The difference between speed and velocity is that speed is a scalar, while velocity is a vector as it includes direction.
How do you calculate the total distance from the average speed?
The total distance is calculated from the average speed by multiplying the average speed by the total time taken.
What is acceleration? (Extended Tier Only)
Acceleration is the rate of change of velocity.
True or False?
Acceleration measures the rate of change of velocity. (Extended Tier Only)
True.
Acceleration measures the rate of change of velocity.
State the equation for calculating average acceleration. (Extended Tier Only)
The equation for average acceleration is $a = \frac{∆ v}{∆ t}$
Where:
- $a$ = acceleration in metres per second squared (m/s²)
- $∆ v$ = change in velocity in metres per second (m/s)
- $∆ t$ = time taken in seconds (s)
What units are used to measure acceleration? (Extended Tier Only)
Acceleration is measured in metres per second squared (m/s²).
How can you find the change in velocity? (Extended Tier Only)
You can find the change in velocity by obtaining the difference between final and initial velocity.
What does a positive acceleration indicate? (Extended Tier Only)
A positive acceleration indicates that the object is speeding up.
Define acceleration. (Extended Tier Only)
Acceleration is the change in an object's velocity over time.
What does a negative acceleration indicate? (Extended Tier Only)
Negative acceleration indicates that the object is slowing down.
Define deceleration. (Extended Tier Only)
Deceleration is negative acceleration, it shows an object is slowing down.
What is the acceleration of an object with constant velocity? (Extended Tier Only)
The acceleration of an object with constant velocity is zero.
How do you calculate acceleration from a velocity-time graph? (Extended Tier Only)
Acceleration is calculated as the gradient of a velocity-time graph.
How is direction represented in a numerical value for acceleration? (Extended Tier Only)
The direction of acceleration is represented by a positive or negative value.
Which type of graph shows the distance travelled by a moving object over a period of time?
A distance-time graph shows the distance travelled by a moving object over a period of time.
How is constant speed represented on a distance-time graph?
On a distance time graph, constant speed is represented by a straight line:
- a steeper slope shows a greater constant speed
- a shallower slope shows a lower constant speed
- a flat, horizontal line shows a constant speed of zero
How is changing speed represented on a distance-time graph?
On a distance-time graph, changing speed is represented by a curved line.
State the equation used to find the gradient of a distance-time graph.
The equation used to find the gradient of a distance-time graph is $speed = gradient = \frac{∆ y}{∆ x}$
Where:
- $∆ y$ = change in distance
- $∆ x$ = change in time
Which line on the distance-time graph shows the slowest speed?
On a distance-time graph, the line with the smallest gradient has the slowest speed. This is the shallowest line (the orange line).
True or False?
This distance-time graph shows a stationary object.
True.
A flat, horizontal line on a distance-time graph shows that the object is stationary. The distance the object has travelled is not changing with time.
Describe the motion of the object shown in this distance-time graph.
The object in this distance-time graph has an increasing speed. The distance it travels in each interval of time is increasing; therefore, the line curves upward.
What does a speed-time graph show?
A speed-time graph shows how the speed of a moving object varies with time.
What is constant acceleration on a speed-time graph?
Constant acceleration on a speed-time graph is represented by a straight, sloping line.
True or False?
A gentle slope on a speed-time graph represents large acceleration.
False.
A gentle slope on a speed-time graph represents a small acceleration.
Describe the motion shown in this speed-time graph.
The speed-time graph shows decreasing acceleration.
The change in speed per unit time decreases.
What does a flat, horizontal line represent on a speed-time graph?
A flat, horizontal line indicates that the acceleration is zero, meaning the object is moving at a constant speed.
What does the area under a speed-time graph represent?
The area under a speed-time graph represents the distance travelled by the object.
How do you calculate the total area under a speed-time graph?
The total area under a speed-time graph shows the total distance travelled. The total area is the sum of the areas of each enclosed section (triangle or rectangle).
What is the formula to calculate the area of a triangle?
The formula to calculate the area of a triangle is $A = \frac{1}{2} \times b \times h$
Where:
- $b$ = base of triangle, measured in metres (m) or centimetres (cm)
- $h$ = height of triangle, measured in metres (m) or centimetres (cm)
What is the formula to calculate the area of a rectangle?
The formula to calculate the area of a rectangle is $A = b \times h$
Where:
- $b$ = base of rectangle, measured in metres (m) or centimetres (cm)
- $h$ = height of rectangle, measured in metres (m) or centimetres (cm)
What shape does the area beneath a speed-time graph form for an object with constant speed?
The area under a speed-time graph forms a rectangle.
True or False?
A flat line on a speed-time graph indicates constant acceleration.
False.
A flat line on a speed-time graph indicates constant speed.
True or False?
The starting speed of this object is zero.
False.
The starting speed is not zero because the line does not start from the origin.
Define acceleration of free fall.
Acceleration of free fall is the constant rate at which all objects fall in the absence of air resistance, typically denoted by the symbol $g$ and equal to approximately 9.81 m/s² near the surface of the Earth.
True or False?
All objects fall with the same acceleration in the presence of air resistance.
False.
In the presence of air resistance different objects fall at different accelerations and not at g. In most Physics questions we assume that air resistance is negligible.
What is the value of the constant acceleration of free fall?
The value of the acceleration of free fall is g = 9.81m/s²
True or False?
Acceleration of free fall remains constant regardless of an object's mass.
True.
Acceleration of free fall remains constant regardless of an object's mass.
Define terminal velocity. (Extended Tier Only)
Terminal velocity is the constant speed reached by a falling object when the upward force of drag equals the downward force of weight, resulting in zero acceleration.
What is the equation for weight?
The equation for weight is $W = m g$
Where:
- $W$ = weight measured in newtons (N)
- $m$ = mass measured in kilograms (kg)
- $g$ = acceleration of freefall (m/s²)
Define air resistance.
Air resistance is the frictional force exerted by air particles on objects moving through air, which opposes the direction of motion.
How does air resistance affect the motion of falling objects? (Extended Tier Only)
Air resistance opposes the motion of objects falling through air, exerting an upward force that increases with the object's speed.
True or False?
Air resistance decreases as the speed of a falling object increases. (Extended Tier Only)
False.
Air resistance increases as the speed of a falling object increases.
What is the relationship between the forces of weight and air resistance during free fall? (Extended Tier Only)
During free fall, weight acts downwards while air resistance acts upwards. As the speed of the object increases, air resistance increases until it equals the weight and terminal velocity is reached.
How does terminal velocity affect the acceleration of a falling object? (Extended Tier Only)
Terminal velocity occurs when the acceleration of a falling object becomes zero because the upward drag force equals the downward force of weight, resulting in a constant speed.
True or False?
Air resistance remains constant during the fall of a skydiver. (Extended Tier Only)
False.
The air resistance changes with speed during the fall of a skydiver.
What factors affect the acceleration of freefall? (Extended Tier Only)
The acceleration of free fall is affected by the gravitational field strength. It is independent of the mass of the falling object.
Define weight.
Weight is the gravitational force exerted on an object with mass.