Oct/Nov 2016

A copper wire is marked ‘length 30 m’ and ‘diameter 0.50 mm’. Which instruments would be most suitable for measuring the wire’s length and its diameter accurately?

Physical quantities and measurement techniques

A weightlifter raises some masses to a vertical height of $1.8\,\text{m}$. The gravitational field strength $g$ is $10\,\text{N kg}^{-1}$. As the lift takes place, the gravitational potential energy of the masses rises by $4500\,\text{J}$. What is the total mass lifted?

Energy

What expression is used to calculate power?

Power

Atmospheric pressure is $100\,000\,\text{Pa}$. What force is exerted by the atmosphere on the top surface of a pond with surface area $20\,\text{m}^2$?

Pressure

A large tank contains oil with density $8.5 \times 10^2\,\text{kg m}^{-3}$. The gravitational field strength $g$ is $10\,\text{N kg}^{-1}$. What is the pressure due to the oil $6.0\,\text{m}$ beneath the surface?

Pressure

Air is enclosed in a cylinder by a piston. The piston is then pushed further into the cylinder. How do the pressure and the volume of the air in the syringe change?

Pressure

Which statement explains the way in which a gas exerts pressure on a container?

Particle model

As a liquid evaporates, molecules leave from the surface. Which molecules are the ones that leave, and what happens to the average kinetic energy of the molecules left in the liquid?

Melting, boiling and evaporation

The diagram illustrates changes of state. What are the names of the changes of state $P$, $Q$, $R$ and $S$?

Melting, boiling and evaporation

A boiling liquid takes in thermal energy (heat) at a rate of $450\,\text{W}$. The specific latent heat of vaporisation is $2.7 \times 10^6\,\text{J kg}^{-1}$. What mass of liquid is vaporised in $9.0\,\text{minutes}$?

Melting, boiling and evaporation

Why is a clinical thermometer able to measure small changes in body temperature?

Thermal expansion of solids, liquids and gases

A skydiver drops from rest through the air and attains terminal velocity. What is the skydiver’s acceleration during the fall?

Motion

Which statement concerning the transfer of thermal energy is correct?

Transfer of thermal energy

A phone starts ringing and the display lights up. Which kinds of wave are involved in how the phone works?

General properties of waves

The diagram illustrates the water surface as a wave travels through a ripple tank. Which lengths show the amplitude and the wavelength of the wave?

General properties of waves

Ray OP strikes plane mirror MN at an angle of incidence of $40^{\circ}$. The mirror is then turned by $10^{\circ}$, as shown by the dashed line. The direction of the incident ray OP stays the same. What is the new angle of incidence?

Reflection of light

A light ray strikes the surface of a glass block. The glass has refractive index $1.5$. The refraction angle is $r$. The angle between the refracted ray and the route the light would follow if the glass block were not present is $d$. What are $r$ and $d$?

Refraction of light

The diagram shows a convex lens producing an image I of an object O. It is not drawn to scale. What is the focal length of the lens?

Thin lenses

The scale diagram shows that a lens forms a magnified image. What is the linear magnification produced by the lens?

Thin lenses

Blue and yellow are colours in the visible spectrum. Of these two, which colour has the lower frequency, and which has the greater wavelength?

Electromagnetic spectrum

Which two kinds of electromagnetic radiation are each used to destroy cancerous cells and to detect cracks in metals?

Electromagnetic spectrum

Which property of a sound wave gets larger as the sound becomes louder?

Sound

The diagram illustrates a car moving at constant speed around a circular track. Which arrow indicates the direction of the resultant force acting on the car?

Circular motion

Delicate instruments are often kept inside a box to shield them from unwanted magnetic fields. What material is the box made from, and why is it selected?

Simple magnetism and magnetic fields

A metal sphere carrying a positive charge is positioned exactly halfway between two metal rods that were previously uncharged, with one of the rods connected to earth. Which diagram shows the charges on the rods?

Electrical charge

A wire carrying a current is positioned between the poles of two magnets, as illustrated. In which direction does the force act on the wire?

Forces on a current-carrying conductor

A coil P with $N$ turns is formed from a wire length of $L$. When it is placed between two magnetic poles, the coil carries a current $I$. A comparable coil Q with $2N$ turns is formed from a wire length of $2L$ of the same wire. It also carries a current $I$ when it is placed between the same magnetic poles. Which coil has the larger resistance, and which coil undergoes the larger turning effect?

Forces on a current-carrying conductor

A magnet oscillates vertically above a coil of wire. The lower end of the magnet moves up and down between P and R. At which position is the lower end of the magnet when there is no induced electromotive force (e.m.f.) in the coil?

Electromagnetic induction

Which material is most appropriate for the core of a transformer and which material is most appropriate for the coils in the transformer?

The transformer

The diagram illustrates a cathode-ray tube. The dotted line indicates the route taken by a beam of electrons. The beam strikes the screen at point X and creates a bright spot. P and Q are horizontal plates positioned on either side of the beam. Which change will cause the bright spot to appear at a different position on the screen?

Uses of an oscilloscope

The table shows the colour code used when marking resistors. What is the resistance of the resistor shown in the diagram?

Resistance

What kinds of radiation can be emitted by radioactive nuclei?

The three types of emission

A newly prepared sample of radioactive material has a count rate of 8000 counts per minute. After 20 days, its count rate is 500 counts per minute. What is the half-life of the material?

Half-life

A car is stationary at a red traffic light. As soon as the light turns green, the car begins to move with uniform acceleration. The graph shows this motion. Which quantity is shown on the x-axis, and which quantity is shown on the y-axis?

Motion

Which number is always the same as the proton number of a neutral atom belonging to a radioactive isotope?

The atom

Which of the following statements about mass and weight is correct?

Mass and weight

Each diagram illustrates two forces with the same magnitude. Which diagram shows two forces that form a Newton’s third law pair?

Forces

Two forces with magnitudes $3.0\ \text{N}$ and $4.0\ \text{N}$ act mutually perpendicular to one another. Which diagram represents the resultant $R$ of these forces?

Balanced and unbalanced forces

A workman moves a barrel, whose weight is $2000\,\text{N}$, up a plank that is $2.0\,\text{m}$ long and into a lorry. The back of the lorry stands $0.80\,\text{m}$ above the horizontal road surface. What work is done on the barrel against gravity?

Work

Objects $P$, $Q$ and $R$ each have different masses and different speeds, as given in the table. In what order do they have increasing kinetic energy (smallest first)?

Energy

A piece of copper wire is marked ‘length $30\,\text{m}$’ and ‘diameter $0.50\,\text{mm}$’. Which instruments would be most appropriate for measuring the length and the diameter of the wire accurately?

Physical quantities and measurement techniques

Two forces, X and Y, act on an object to give a resultant force. The scale diagram shows the magnitudes and directions of forces X and Y. Force Z balances the resultant force from X and Y and keeps the object at rest. Which arrow shows force Z?

Balanced and unbalanced forces

Three objects P, Q and R each have different masses and different speeds, as listed in the table. Masses: $P = 1.0\,\text{kg}$, $Q = 2.0\,\text{kg}$, $R = 5.0\,\text{kg}$. Speeds: $P = 3.0\,\text{m s}^{-1}$, $Q = 2.0\,\text{m s}^{-1}$, $R = 1.0\,\text{m s}^{-1}$. In what order should the objects be placed for increasing kinetic energy (smallest first)?

Energy

Which power stations depend entirely on renewable energy sources?

Energy resources

Which force performs no work?

Circular motion

A workman pushes a barrel with weight $2000\,\text{N}$ along a plank that is $2.0\,\text{m}$ long and up into a lorry. The rear of the lorry is $0.80\,\text{m}$ above the level road surface. What is the work done on the barrel against gravity?

Work

An electric motor is used to run a lift (elevator). The motor does $140\,000\,\text{J}$ of work in $70\,\text{s}$. Calculate the output power of the motor.

Power

Which equation represents the efficiency of an a.c. generator?

The a.c. generator

A manometer is used to measure the pressure of the gas supply in the laboratory. Which distance indicates the gas pressure above atmospheric pressure?

Pressure

A gas undergoes a slow expansion while its temperature stays unchanged. What occurs to the gas molecules?

Particle model

An image of a sheet ripped from an exercise book is shown. “…and some particles at the surface acquire enough kinetic energy to escape, carrying that energy away with them.” Which process is this describing?

Melting, boiling and evaporation

A skydiver drops from rest through the air and attains terminal velocity. What acceleration does the skydiver have while falling?

Balanced and unbalanced forces

A liquid sample at $100\,^\circ\text{C}$ is left to cool until it reaches a room temperature of $20\,^\circ\text{C}$. The graph shows the way the temperature varies with time as the sample cools. At what time is the sample fully solidified?

Melting, boiling and evaporation

To increase the temperature of one kilogram of water by $1\degree\text{C}$, more thermal energy is needed than for one kilogram of copper. Why does this happen?

Specific heat capacity

An electric heater produces thermal energy for three minutes, and this is used to melt wax. At the start, the wax is already at its melting point of $60\degree\text{C}$. The specific latent heat of the wax is $220\ \text{J g}^{-1}$. The heater transfers $7700\ \text{J}$ of thermal energy to the wax. How much wax melts?

Melting, boiling and evaporation

Why is a clinical thermometer appropriate for detecting small changes in body temperature?

Thermal expansion of solids, liquids and gases

In which states of matter does convection take place?

Convection

Which of the following statements about waves is correct?

General properties of waves

The diagram illustrates the water surface in a ripple tank as a wave moves across it. Which lengths show the amplitude and the wavelength of the wave?

General properties of waves

A lens is used to form a magnified image, as illustrated by the scale diagram. What is the linear magnification produced by the lens?

Thin lenses

A girl has long-sightedness. Which of the following statements is correct?

Thin lenses

Sound moves through solids, liquids and gases at different speeds. Which list arranges these states of matter in increasing order of speed of sound (from slowest to fastest)?

Sound

Aluminium spheres P and Q, with masses $0.50\,\text{kg}$ and $1.0\,\text{kg}$ respectively, are let go together from the same height. Why do they experience the same acceleration?

Motion

A man is positioned between two tall buildings, $P$ and $Q$. This sketch is not to scale. He is $50\ \text{m}$ away from $P$ and $200\ \text{m}$ away from $Q$. He discharges a gun, and the first two echoes that he hears are $1.0\ \text{s}$ apart. Calculate the speed of sound from this observation.

Sound

Sensitive instruments are often put inside a box so that stray magnetic fields do not affect them. What material is used for the box, and why is this material selected?

Simple magnetism and magnetic fields

A positively charged metal sphere is positioned halfway between two metal rods that were both initially uncharged, with one of the rods connected to earth. Which diagram shows the charges on the rods?

Electrical charge

When finding the power produced by a heater, an ammeter and a voltmeter are placed in the circuit as shown. In relation to the heater, how are these meters connected?

Circuit diagrams and circuit components

Resistors with different resistances are linked to a power supply in either a parallel circuit or a series circuit. Which statement is correct?

Series and parallel circuits

A car’s headlamp circuit contains a $7\,\text{A}$ fuse. What is the function of the fuse?

Electrical safety

A current-carrying wire is placed between the poles of two magnets, as illustrated. In which direction does the force act on the wire?

Forces on a current-carrying conductor

A magnet is moved vertically up and down above a wire coil. The lower end of the magnet travels up and down between P and R. At what position is the lower end of the magnet when no induced electromotive force (e.m.f.) is produced in the coil?

Electromagnetic induction

A battery is connected in series with a thermistor and a resistor whose resistance remains constant. A voltmeter is placed in parallel across the resistor. As the temperature decreases, what changes are correct?

Series and parallel circuits

A newly prepared sample of radioactive material has a count rate of $8000$ counts per minute. After $20$ days, its count rate falls to $500$ counts per minute. What is the half-life of the material?

Half-life

The diagram is a distance-time graph for a car moving along a straight line. In which region is the car decelerating?

Motion

A uranium nucleus $^{238}_{92}\text{U}$ undergoes decay to thorium by releasing an alpha-particle. What thorium nucleus is formed as a result?

The three types of emission

A $20\,\text{N}$ force pushes an object of mass $5.0\,\text{kg}$ forwards. Another force also acts on the object. The object has a forward acceleration of $3.0\,\text{m s}^{-2}$. What are the magnitude and direction of the other force?

Balanced and unbalanced forces

The diagram depicts a car moving at constant speed around a circular track. Which arrow indicates the direction of the resultant force acting on the car?

Circular motion

A block is suspended from a spring balance. The block pulls the marker inside the balance downward. What can the marker’s position be used to determine?

Mass and weight

Gold has a density of $19\,\text{g cm}^{-3}$. A gold coin has a thickness of $2.0\,\text{mm}$. The area of each face of the coin is $4.5\,\text{cm}^2$. What is the coin's mass?

Density

A man who has an open parachute is descending towards Earth at constant speed. The forces acting are shown below. P: the upward force exerted by the parachute on the man. Q: the upward force exerted by the man on the Earth. R: the downward force exerted by the Earth on the parachute. S: the downward force exerted by the man on the parachute. Which two forces form a Newton’s third law pair?

Forces

A car with a mass of 800 kg is moving at 25 m/s on a straight, level road.

Motion

One specific cooking oil remains liquid when it is at room temperature.

Thermal properties and temperature

Fig. 2.1 illustrates a bed that folds up against a wall in the daytime. In the horizontal position, it is held up on one side by a hinge and on the other side by two legs. The weight $W$ of the bed acts through its centre of mass, which is $0.35\,\text{m}$ horizontally from the hinge.

Turning effect of forces

A major power station burns oil in order to heat water inside a boiler.

Efficiency

A lamp sits at the base of a shallow pool of water. The critical angle for light travelling from water into air is $49^\circ$.

Refraction of light

Fig. 5.1 shows a loudspeaker positioned inside a glass bell-jar containing air. The loudspeaker emits a sound with frequency $2200\,\text{Hz}$.

Sound

Two flexible iron strips, WX and YZ, are positioned close together inside a solenoid (long coil). The end W of WX and the end Z of YZ are fixed firmly in place. Fig. 6.1 shows the solenoid connected to a d.c. power supply and a switch. When the switch is closed, an electric current flows in the solenoid. End W of flexible iron strip WX becomes a magnetic S-pole.

Magnetic effect of a current

A house’s a.c. mains electricity system has three wires: live, neutral and earth.

Electrical safety

Sodium-24 and sodium-23 are two isotopes of sodium. During decay, sodium-24 is radioactive and gives out beta-particles together with gamma-rays.

Radioactivity

The primary coil of a transformer is linked to the $230\,\text{V}$ a.c. mains supply.

The transformer

Starting from rest, a skier moves in a straight line with uniform acceleration of $3.4\,\text{m s}^{-2}$ for $5.0\,\text{s}$.

Motion

A laser emits a beam of red light.

Refraction of light

A skateboarder with mass $45\,\text{kg}$ is positioned at the top of a ramp. Figure 2.1 illustrates the skateboarder and the ramp. The skateboarder moves vertically downward by $1.8\,\text{m}$. The gravitational field strength $g$ is $10\,\text{N kg}^{-1}$.

Circular motion

When a freezer lid is lifted, it turns about the hinge at the back of the freezer, while the handle is located at the front. Fig. 3.1 shows a side view of the freezer. The handle is $0.70\,\text{m}$ from the hinge. The lid has a mass of $2.0\,\text{kg}$. The gravitational field strength $g$ is $10\,\text{N kg}^{-1}$.

Turning effect of forces

Fig. 4.1 depicts a kettle of water on the burner of a gas cooker. The gas burner is ignited at time $t = 0$. By $t = 250\,\text{s}$, the water reaches $100^{\circ}\text{C}$, which is the boiling point of water.

Melting, boiling and evaporation

Gas is contained in a syringe by a piston, while the narrow end of the syringe is sealed, as illustrated in Fig. 5.1. When the gas is at a pressure of $1.1 \times 10^{5}\,\text{Pa}$, it has a volume of $40\,\text{cm}^3$.

Particle model

Inside a cathode-ray oscilloscope (c.r.o.), an electron beam is generated by a filament at one end of an evacuated glass tube. The electrons are then accelerated and hit a screen at the opposite end of the tube.

Magnetic effect of a current

Plutonium-238 is a radioactive isotope that undergoes decay by emitting alpha-particles. It also gives off gamma-rays.

Radioactivity

A spring is removed from a drawer in a physics laboratory.

Elastic deformation

A vertical solenoid (long coil) containing an iron core is clamped in a wooden holder above a laboratory bench. The solenoid is joined in series to a battery, a switch S, an ammeter and a variable resistor. A voltmeter is connected across the solenoid in parallel.

Magnetic effect of a current

A student studies how surface area changes the rate at which water evaporates at room temperature.

Melting, boiling and evaporation

A student studies how changing the ramp height changes the distance a toy car moves along the floor, as shown in Fig. 2.1. The car is put at the top of the ramp at position A and then let go. It moves down the ramp and then across the horizontal floor, coming to rest at position B. While moving down the ramp, the car drops through a vertical distance $h$. After that, it travels a distance $l$ along the floor.

Physical quantities and measurement techniques

A student is finding the specific heat capacity of aluminium. The equipment supplied includes a thermometer, a heater, an aluminium block of mass $1.00\,\text{kg}$ with holes for the heater and thermometer, a d.c. power supply, an ammeter, a voltmeter and a stop-clock.

Specific heat capacity

A student receives a box that contains ten similar plastic drinking straws, together with a $30\,\text{cm}$ ruler and two set-squares.

Physical quantities and measurement techniques

A student wants to find the density of a liquid. She transfers the liquid into a measuring cylinder, as shown in Fig. 1.1.

Density

The pencil lead is the carbon core inside a pencil. Because it is carbon, it conducts electricity.

Resistance

A student examines current in a diode. The appearance of the student’s graph is shown in Fig. 3.1.

Circuit diagrams and circuit components

A student is handed a lump of Blu-Tack and shapes it into a cube. The cube’s front face is shown full size in Fig. 4.1.

Physical quantities and measurement techniques