GCSE Combined Science Physic Paper 2

Give an example of a scalar quantity.

Speed, distance, mass, temperature, or time.

Give an example of a vector quantity.

Force, velocity, displacement, acceleration, or momentum.

What is a contact force?

A force where the interacting objects are physically touching (e.g., friction, air resistance).

What is a non-contact force?

A force that acts without the objects touching (e.g., gravitational, magnetic, electrostatic).

What is the interaction pair to the Earth pulling an apple downwards?

The apple pulling the Earth upwards with an equal gravitational force.

What is the difference between mass and weight?

Mass is the amount of matter (kg) and is constant. Weight is the force due to gravity (N) and changes with location.

State the formula that links weight, mass, and gravitational field strength.

W = m g

What is the value of the gravitational field strength (g) on Earth?

Approximately 9.8 N/kg (or m/s²).

What is the resultant force?

The single force that has the same effect as all the individual forces acting on an object.

What happens to an object if the resultant force on it is zero?

It remains stationary or continues to move at a constant velocity.

State the formula for work done.

W = F s (Work done = force × distance moved in the direction of the force).

What is the unit of work done?

Joule (J).

What is elastic deformation?

When an object returns to its original shape after the force is removed.

What is inelastic deformation?

When an object does not return to its original shape after the force is removed.

State Hooke's Law (formula).

F = k e (Force = spring constant × extension).

What is the limit of proportionality?

The point beyond which force and extension are no longer directly proportional.

State the formula for elastic potential energy stored in a spring.

E = 1/2 k e²

What is the difference between distance and displacement?

Distance is a scalar (total path length). Displacement is a vector (straight-line distance and direction from start to finish).

What is the difference between speed and velocity?

Speed is a scalar (how fast). Velocity is a vector (speed in a given direction).

State the formula for average speed.

v = s / t (speed = distance / time).

What is a typical speed for a person walking?

About 1.5 m/s.

State the formula for acceleration.

a = Δv / t (acceleration = change in velocity / time taken).

What is uniform acceleration?

Constant acceleration.

State the equation linking initial velocity (u), final velocity (v), acceleration (a), and distance (s) for uniform acceleration.

v² - u² = 2 a s

On a distance-time graph, what does the gradient represent?

Speed.

What does a flat (horizontal) line on a distance-time graph represent?

The object is stationary.

On a velocity-time graph, what does the gradient represent?

Acceleration.

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

Distance travelled.

What is terminal velocity?

The constant maximum velocity reached by a falling object when drag equals weight (resultant force = 0).

State Newton's First Law.

An object remains at rest or moves with constant velocity unless acted upon by a resultant force.

State Newton's Second Law (formula).

F = m a (Resultant force = mass × acceleration).

State Newton's Third Law.

When two objects interact, they exert equal and opposite forces on each other.

What is the relationship between resultant force and acceleration?

Acceleration is directly proportional to the resultant force (if mass is constant).

What is the relationship between mass and acceleration?

Acceleration is inversely proportional to mass (if force is constant).

What is stopping distance?

The sum of thinking distance and braking distance.

List two factors that affect thinking distance.

Speed, reaction time, tiredness, drugs/alcohol, or distractions.

List two factors that affect braking distance.

Speed, road conditions, tyre condition, or brake condition.

During braking, what energy transfer takes place?

Kinetic energy is transferred to thermal energy in the brakes (and tyres/road).

What is a typical range for human reaction time?

0.2 to 0.9 seconds.

In the ruler drop test, what does the distance the ruler falls represent?

It is used to calculate the reaction time of the person catching it.

What do waves transfer?

Energy.

Do waves transfer matter?

No.

What is a medium?

The substance through which a wave travels (e.g., air, water).

What is the main difference between transverse and longitudinal waves?

In transverse waves, vibrations are perpendicular to energy transfer. In longitudinal waves, vibrations are parallel.

Give an example of a transverse wave.

Light (or any EM wave), ripples on water, waves on a string.

Give an example of a longitudinal wave.

Sound waves in air.

In a longitudinal wave, what are the regions of high pressure called?

Compressions.

Define amplitude.

The maximum displacement of a point on a wave from its rest position.

Define wavelength (λ).

The distance between two identical points on consecutive waves (e.g., crest to crest).

Define frequency (f).

The number of complete waves passing a point per second (measured in Hz).

What is the period (T) of a wave?

The time taken for one complete wave to pass a point.

State the equation linking wave speed (v), frequency (f), and wavelength (λ).

v = f λ

In the ripple tank method for measuring wave speed, what does the shadow on the screen represent?

The pattern of the water wave ripples.

Why does refraction occur?

Because the wave changes speed as it crosses a boundary between two different media.

What is the speed of all electromagnetic waves in a vacuum?

3 × 10⁸ m/s.

List the seven groups of the electromagnetic spectrum in order of increasing frequency.

Radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, gamma rays.

Which part of the EM spectrum is detectable by the human eye?

Visible light.

What are two main uses of microwaves?

Satellite communications and microwave ovens.

What type of EM wave is used in fibre optic communication?

Visible light (or infrared).

What property of ultraviolet radiation makes it dangerous?

It can damage skin cells and cause cancer (it is ionising).

Why are X-rays and gamma rays dangerous?

They are ionising radiation and can damage cells/DNA, leading to cancer.

What unit is used to measure radiation dose/risk?

Sieverts (Sv) or millisieverts (mSv).

In the infrared absorption experiment with metal plates, which surface (black or white) causes the ball to drop first and why?

The black surface, because it absorbs infrared radiation more effectively, heating up faster.

What are the two poles of a magnet?

North and South.

What is the force between two like poles?

Repulsion.

What is the force between two unlike poles?

Attraction.

Name three magnetic materials.

Iron, steel (alloy of iron), nickel, cobalt.

What is a magnetic field?

The region around a magnet where a magnetic force can be detected.

Where is a magnetic field strongest?

At the poles.

What does the direction of a magnetic field line show?

The direction of the force on a north pole placed in the field (from North to South).

What does a compass contain?

A small bar magnet (or magnetic needle).

Why does a compass needle point north?

It aligns with the Earth's magnetic field.

What is the difference between a permanent and an induced magnet?

A permanent magnet produces its own field. An induced magnet becomes magnetic only when in another field and loses magnetism when removed.

What is created around a wire when an electric current flows?

A magnetic field.

What is the shape of the magnetic field around a straight current-carrying wire?

Concentric circles.

How can you reverse the direction of the magnetic field around a wire?

Reverse the direction of the current.

State the right-hand thumb rule for a straight wire.

Thumb points in direction of conventional current; curled fingers show direction of magnetic field lines.

What is a solenoid?

A long coil of wire.

What is the shape of the magnetic field inside a long solenoid?

Strong, uniform, and parallel.

Outside a solenoid, the magnetic field pattern resembles that of what?

A bar magnet.

Name three ways to increase the strength of the magnetic field of a solenoid.

Increase the current, add more turns of wire, or insert an iron core.

What is an electromagnet?

A solenoid with a soft iron core that becomes magnetic when current flows.

What is a key advantage of an electromagnet over a permanent magnet?

It can be switched on and off (and its strength can be varied).