State the quantity and SI unit represented by each SUVAT symbol: s , u , v , a , t

s = displacement (m) u = initial velocity (m s -1 ) v = final velocity (m s -1 ) a = acceleration (m s -2 ) t = time interval (s)

The SUVAT equations can be used only when acceleration is ..........

The SUVAT equations can be used only when acceleration is constant (and not zero)

What is the acceleration of an object in freefall when air resistance is negligible?

9.81 m s -2 , directed vertically downwards

True or False? An object thrown straight upwards has zero acceleration at the highest point of its path

False. At the highest point the velocity is momentarily zero, but the acceleration is still 9.81 m s -2 downwards

What sign does acceleration take for an object that is slowing down?

Negative A decelerating object has a negative acceleration, which must be included in SUVAT calculations

On a displacement–time graph, what does the slope represent?

The velocity A straight slope is constant velocity; a curved slope is acceleration

On a velocity–time graph, what does the area under the line represent?

The displacement (distance travelled)

On a displacement–time graph, a curved slope represents an ..........

On a displacement–time graph, a curved slope represents an acceleration

True or False? The area under a displacement–time graph gives the distance travelled

False. The area under a displacement–time graph is meaningless It is the slope of a displacement–time graph that gives velocity

When choosing a scale for a graph axis, which multiples should be avoided?

Multiples of 3 Use increments in multiples of 2, 5 or 10 so plotting is accurate and the line fills the axes

Define non-uniform acceleration on a velocity–time graph

Acceleration that changes over time It is shown by a curved line on a velocity–time graph (uniform acceleration is a straight line)

Define instantaneous velocity

The velocity at a single point in time It is found by drawing a tangent to a curved line and calculating the slope of that tangent

How do you find the slope of a curved line at a given point?

Draw a tangent to the curve at that point, then find the slope of the tangent Make the tangent as long as will fit on the graph

Describe how to find the area under a curved line on a motion graph

Divide the shape into rectangles and triangles Calculate the area of each Count any remaining whole squares Add the totals together

To find a slope accurately, choose two points that are as .......... as possible on the line

To find a slope accurately, choose two points that are as far apart as possible on the line

True or False? Non-uniform acceleration produces a straight-line velocity–time graph

False. Non-uniform acceleration produces a curved velocity–time graph A straight line represents uniform (constant) acceleration

Why does a skydiver's acceleration decrease as they fall towards terminal velocity?

As speed increases, air resistance increases This reduces the resultant force against the motion, so acceleration falls When weight and air resistance balance , acceleration becomes zero

A quantity that has magnitude but no direction For example, mass

A quantity that has both magnitude and direction For example, weight

.......... is the length and direction of a straight line from the starting point to the finishing point

Displacement is the length and direction of a straight line from the starting point to the finishing point

Give two examples each of scalar and vector quantities

Scalars: distance, speed, mass, time, energy (also volume, density, pressure, charge, temperature) Vectors: displacement, velocity, acceleration, force, momentum

True or False? An object moving at constant speed must also have constant velocity

False. An object can have constant speed but changing velocity if it is changing direction Velocity is a vector, so a change in direction changes the velocity

Is acceleration a scalar or a vector quantity?

A vector It has both magnitude and direction

What is the difference between distance and displacement?

Distance is the total path length travelled — a scalar Displacement is the straight-line length and direction from start to finish — a vector

How are vector quantities distinguished from scalars in notation?

By writing them in bold italic (for example, F or s ), or with an arrow above the symbol The arrow shows only that the quantity has a direction, not the actual direction

Define the components of a vector.

The two vectors into which a single resultant vector is resolved, which in combination have the same effect as the original vector

The length of a vector arrow represents its .......... , while the arrowhead shows its ..........

The length of a vector arrow represents its magnitude , while the arrowhead shows its direction

True or False? A sketch used to resolve vectors by calculation must be drawn exactly to scale.

False. Only the scale drawing method needs accurate lengths and angles. When resolving by calculation a rough labelled sketch is enough, since trigonometry gives the values

Name the two methods used to resolve a vector into its components.

Scale drawing — carefully producing a drawing with correct lengths and angles using a pencil, ruler and protractor Calculation — using trigonometry (soh-cah-toa) on a labelled sketch

Define the resultant vector .

The single vector (also called the 'net' vector) that has the same effect as two or more vectors combined by adding or subtracting them

How do you combine two vectors using the triangle method ?

Link the vectors head-to-tail The resultant is formed by connecting the tail of the first vector to the head of the second vector

How do you combine two vectors using the parallelogram method ?

Link the vectors tail-to-tail Complete the parallelogram The resultant is the diagonal of the parallelogram

For two perpendicular vectors, the magnitude of the resultant is found using .......... , and its direction is found using ..........

For two perpendicular vectors, the magnitude of the resultant is found using Pythagoras' theorem , and its direction is found using trigonometry

True or False? Vectors that are not perpendicular should be added by calculation.

False. Adding by calculation (Pythagoras and trigonometry) applies when the vectors are perpendicular . When they are not perpendicular , a scale drawing is used instead

Define the time of flight of a projectile.

How long the projectile is in the air

Define the maximum height of a projectile.

The height at which the projectile is momentarily at rest — its vertical velocity is zero

The .......... of a projectile is the horizontal distance it travels.

The range of a projectile is the horizontal distance it travels

Once a projectile has been released, the only force acting on it is ..........

Once a projectile has been released, the only force acting on it is gravity

State the two considerations used to solve two-dimensional projectile motion problems.

Constant velocity in the horizontal direction Constant acceleration (due to gravity) in the perpendicular vertical direction

True or False? A projectile's horizontal velocity changes during flight.

False. Ignoring air resistance, the horizontal velocity is constant — gravity acts vertically, so only the vertical component of velocity changes during flight

Name the three scenarios of projectile motion.

Vertical projection Horizontal projection Projection at an angle

Define a free-body diagram .

A diagram that models the forces acting on an object , with each force drawn as a labelled vector arrow and the body shown free from contact with any other object

In a free-body diagram, state the three features of each force arrow.

Scaled to the magnitude of the force it represents Points in the direction the force acts Labelled with the name of the force or an appropriate symbol

Three forces acting on an object in equilibrium form a closed ..........

Three forces acting on an object in equilibrium form a closed vector triangle

Define an extended rigid body .

An object in which all parts stay in the same position relative to each other when the object moves

State the three forces acting on a box sliding down a slope, and the direction of each.

Normal contact force , R — acts perpendicular to the slope Friction , F — acts parallel to the slope, opposite to the direction of motion Weight , W — acts vertically down towards the Earth

True or False? A free-body diagram includes the forces the object exerts on others.

False. A free-body diagram shows only the forces acting on the chosen object, drawn free from contact with other objects — not the forces it exerts on them

A LevelPhysicsEdexcelFlashcards2. MechanicsMotion

Motion (Edexcel A Level Physics): Flashcards

Exam code: 9PH0

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FrontEquations of Motion
What are the four SUVAT equations?
BackEquations of Motion
The four SUVAT equations are:
$v = u + a t$
$v^{2} = u^{2} + 2 a s$
$s = u t + \frac{1}{2} a t^{2}$
$s = \frac{(u + v)}{2} t$
The letters stand for displacement (s), initial velocity (u), final velocity (v), acceleration (a) and time (t)
BackEquations of Motion
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FrontEquations of Motion
State the quantity and SI unit represented by each SUVAT symbol: s, u, v, a, t
BackEquations of Motion
s = displacement (m)
u = initial velocity (m s^-1)
v = final velocity (m s^-1)
a = acceleration (m s^-2)
t = time interval (s)

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Cards in this collection (55)

What are the four SUVAT equations?
The four SUVAT equations are:
- $v = u + a t$
- $v^{2} = u^{2} + 2 a s$
- $s = u t + \frac{1}{2} a t^{2}$
- $s = \frac{(u + v)}{2} t$
The letters stand for displacement (s), initial velocity (u), final velocity (v), acceleration (a) and time (t)
State the quantity and SI unit represented by each SUVAT symbol: s, u, v, a, t
- s = displacement (m)
- u = initial velocity (m s^-1)
- v = final velocity (m s^-1)
- a = acceleration (m s^-2)
- t = time interval (s)
The SUVAT equations can be used only when acceleration is ..........
The SUVAT equations can be used only when acceleration is constant (and not zero)
Which SUVAT equation does not contain time t?
$v^{2} = u^{2} + 2 a s$
What is the acceleration of an object in freefall when air resistance is negligible?
9.81 m s^-2, directed vertically downwards
True or False?
An object thrown straight upwards has zero acceleration at the highest point of its path
False.
At the highest point the velocity is momentarily zero, but the acceleration is still 9.81 m s^-2 downwards
What sign does acceleration take for an object that is slowing down?
Negative
A decelerating object has a negative acceleration, which must be included in SUVAT calculations
On a displacement–time graph, what does the slope represent?
The velocity
A straight slope is constant velocity; a curved slope is acceleration
On a velocity–time graph, what does the slope represent?
The acceleration
On a velocity–time graph, what does the area under the line represent?
The displacement (distance travelled)
On an acceleration–time graph, what does the area under the line represent?
The change in velocity
On a displacement–time graph, a curved slope represents an ..........
On a displacement–time graph, a curved slope represents an acceleration
True or False?
The area under a displacement–time graph gives the distance travelled
False.
The area under a displacement–time graph is meaningless
It is the slope of a displacement–time graph that gives velocity
When choosing a scale for a graph axis, which multiples should be avoided?
Multiples of 3
Use increments in multiples of 2, 5 or 10 so plotting is accurate and the line fills the axes
Define non-uniform acceleration on a velocity–time graph
Acceleration that changes over time
It is shown by a curved line on a velocity–time graph (uniform acceleration is a straight line)
Define instantaneous velocity
The velocity at a single point in time
It is found by drawing a tangent to a curved line and calculating the slope of that tangent
How do you find the slope of a curved line at a given point?
Draw a tangent to the curve at that point, then find the slope of the tangent
Make the tangent as long as will fit on the graph
Describe how to find the area under a curved line on a motion graph
- Divide the shape into rectangles and triangles
- Calculate the area of each
- Count any remaining whole squares
- Add the totals together
To find a slope accurately, choose two points that are as .......... as possible on the line
To find a slope accurately, choose two points that are as far apart as possible on the line
What is the formula for the area of a triangle?
$area = \frac{1}{2} \times base \times height$
True or False?
Non-uniform acceleration produces a straight-line velocity–time graph
False.
Non-uniform acceleration produces a curved velocity–time graph
A straight line represents uniform (constant) acceleration
Why does a skydiver's acceleration decrease as they fall towards terminal velocity?
As speed increases, air resistance increases
This reduces the resultant force against the motion, so acceleration falls
When weight and air resistance balance, acceleration becomes zero
Define scalar
A quantity that has magnitude but no direction
For example, mass
Define vector
A quantity that has both magnitude and direction
For example, weight
.......... is the length and direction of a straight line from the starting point to the finishing point
Displacement is the length and direction of a straight line from the starting point to the finishing point
Give two examples each of scalar and vector quantities
Scalars: distance, speed, mass, time, energy (also volume, density, pressure, charge, temperature)
Vectors: displacement, velocity, acceleration, force, momentum
True or False?
An object moving at constant speed must also have constant velocity
False.
An object can have constant speed but changing velocity if it is changing direction
Velocity is a vector, so a change in direction changes the velocity
Is acceleration a scalar or a vector quantity?
A vector
It has both magnitude and direction
What is the difference between distance and displacement?
Distance is the total path length travelled — a scalar
Displacement is the straight-line length and direction from start to finish — a vector
How are vector quantities distinguished from scalars in notation?
By writing them in bold italic (for example, F or s), or with an arrow above the symbol
The arrow shows only that the quantity has a direction, not the actual direction
Define the components of a vector.
The two vectors into which a single resultant vector is resolved, which in combination have the same effect as the original vector
A vector of magnitude F acts at angle θ to the horizontal. Write expressions for its horizontal and vertical components.
Horizontal: $F_{x} = F \cos θ$
Vertical: $F_{y} = F \sin θ$
The length of a vector arrow represents its .........., while the arrowhead shows its ..........
The length of a vector arrow represents its magnitude, while the arrowhead shows its direction
True or False?
A sketch used to resolve vectors by calculation must be drawn exactly to scale.
False.
Only the scale drawing method needs accurate lengths and angles. When resolving by calculation a rough labelled sketch is enough, since trigonometry gives the values
Name the two methods used to resolve a vector into its components.
- Scale drawing — carefully producing a drawing with correct lengths and angles using a pencil, ruler and protractor
- Calculation — using trigonometry (soh-cah-toa) on a labelled sketch
When resolving a vector, which component is found using cos *θ*?
The component adjacent to the angle — the one the resultant is closing down onto — is found using $\cos θ$
The component opposite the angle uses $\sin θ$
Define the resultant vector.
The single vector (also called the 'net' vector) that has the same effect as two or more vectors combined by adding or subtracting them
How do you combine two vectors using the triangle method?
- Link the vectors head-to-tail
- The resultant is formed by connecting the tail of the first vector to the head of the second vector
How do you combine two vectors using the parallelogram method?
- Link the vectors tail-to-tail
- Complete the parallelogram
- The resultant is the diagonal of the parallelogram
For two perpendicular vectors, the magnitude of the resultant is found using .........., and its direction is found using ..........
For two perpendicular vectors, the magnitude of the resultant is found using Pythagoras' theorem, and its direction is found using trigonometry
True or False?
Vectors that are not perpendicular should be added by calculation.
False.
Adding by calculation (Pythagoras and trigonometry) applies when the vectors are perpendicular. When they are not perpendicular, a scale drawing is used instead
A swimmer heads due north at 2 m s^-1 across a current flowing east at 5 m s^-1. Calculate the magnitude of the resultant velocity.
$R = \sqrt{2^{2} + 5^{2}} = \sqrt{29} \approx 5.4 {m s}^{- 1}$
Direction: $θ = \tan^{- 1} (\frac{2}{5}) \approx 22 °$ to the horizontal
Define the time of flight of a projectile.
How long the projectile is in the air
Define the maximum height of a projectile.
The height at which the projectile is momentarily at rest — its vertical velocity is zero
The .......... of a projectile is the horizontal distance it travels.
The range of a projectile is the horizontal distance it travels
Once a projectile has been released, the only force acting on it is ..........
Once a projectile has been released, the only force acting on it is gravity
State the two considerations used to solve two-dimensional projectile motion problems.
- Constant velocity in the horizontal direction
- Constant acceleration (due to gravity) in the perpendicular vertical direction
True or False?
A projectile's horizontal velocity changes during flight.
False.
Ignoring air resistance, the horizontal velocity is constant — gravity acts vertically, so only the vertical component of velocity changes during flight
Name the three scenarios of projectile motion.
- Vertical projection
- Horizontal projection
- Projection at an angle
Define a free-body diagram.
A diagram that models the forces acting on an object, with each force drawn as a labelled vector arrow and the body shown free from contact with any other object
In a free-body diagram, state the three features of each force arrow.
- Scaled to the magnitude of the force it represents
- Points in the direction the force acts
- Labelled with the name of the force or an appropriate symbol
Three forces acting on an object in equilibrium form a closed ..........
Three forces acting on an object in equilibrium form a closed vector triangle
Define an extended rigid body.
An object in which all parts stay in the same position relative to each other when the object moves
State the three forces acting on a box sliding down a slope, and the direction of each.
- Normal contact force, R — acts perpendicular to the slope
- Friction, F — acts parallel to the slope, opposite to the direction of motion
- Weight, W — acts vertically down towards the Earth
True or False?
A free-body diagram includes the forces the object exerts on others.
False.
A free-body diagram shows only the forces acting on the chosen object, drawn free from contact with other objects — not the forces it exerts on them

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