Oct/Nov 2018

What could be the mass of a normal adult person?

Mass and weight

A piston traps air inside a cylinder. The air pressure is $p$ and the air column has a length of $20\ \text{cm}$. The piston is then pulled outwards until the air column is $40\ \text{cm}$ longer than before. The temperature of the air stays constant. What is the air pressure now?

Particle model

A long tube filled with mercury is turned upside down into a small dish of mercury. The mercury level inside the tube drops, so a vacuum remains at the top. When atmospheric pressure falls, which length becomes smaller?

Pressure

A gas is enclosed in a sealed container. The gas is then cooled while the container volume remains unchanged. What happens to the gas molecules?

Particle model

The diagram illustrates four changes of state W, X, Y and Z. Which row states the names of these four changes of state?

States of matter

What gets larger when a liquid changes into a gas at its boiling point?

Melting, boiling and evaporation

A glass jar has a metal lid fitted tightly onto it. Which process would make it easier to take the lid off the jar?

Thermal expansion of solids, liquids and gases

The specific heat capacity of lead is $130\ \text{J kg}^{-1}\,^{\circ}\text{C}^{-1}$. A lead sample with mass $0.50\ \text{kg}$ is raised from $10^{circ}\text{C}$ to $35^{\circ}\text{C}$. Which calculation gives the amount of thermal energy, in J, absorbed by the lead?

Specific heat capacity

A cold solid is put on top of a hot solid. Thermal energy moves from the hot solid to the cold solid. What explains this?

Conduction

What term means the number of wave crests passing a point each second?

General properties of waves

The diagram depicts a thin converging lens with focal length $f$. At what position should an object be placed so that a real image forms at the location shown?

Thin lenses

A small cylinder is moved along a ruler and makes two complete revolutions. Circumference means the distance all the way around the edge of a circle. What is the cylinder's circumference?

Physical quantities and measurement techniques

White light is split up by a prism. In contrast to blue light, red light is

Dispersion of light

What is the approximate value of $\frac{\text{speed of light in air}}{\text{speed of sound in air}}$ ?

General properties of waves

What are the lowest and highest frequencies of sound that a person with normal hearing can detect?

Sound

Ultrasound has several applications in engineering and medicine. For which purpose is ultrasound not used?

Sound

Which diagram illustrates the electric field surrounding a single positive point charge?

Electrical charge

Two isolated charges P and Q, equal in magnitude but opposite in sign, create an electric field. How does the field at X differ from the field at Y?

Electrical charge

A positively charged rod is brought near an insulated metal sphere. The sphere is connected to earth, as shown. The earth link is then taken away, and after that the rod is removed. Which diagram indicates the charges on the sphere once the rod has been removed?

Electrical charge

The voltage across a resistor with constant resistance varies. Which graph illustrates how the current in the resistor varies with the voltage?

Resistance

A wire with length $0.50\,\text{m}$ and cross-sectional area $1.0 \times 10^{-6}\,\text{m}^2$ has a resistance of $0.75\,\Omega$. A second wire made from the same material has length $2.0\,\text{m}$ and cross-sectional area $0.50 \times 10^{-6}\,\text{m}^2$. What is the resistance of this longer wire?

Resistance

A battery with electromotive force (e.m.f.) $10\,\text{V}$ is connected to a resistor. A charge of $2.0\,\text{C}$ travels through the resistor. How much work is done as the charge moves through the resistor?

Electromotive force and potential difference

A skydiver is descending at terminal velocity. Which row gives the skydiver’s acceleration and the skydiver’s velocity?

Motion

Three matching resistors are connected in series to a cell. Voltmeter Q gives a reading of $8.0\,\text{V}$. What value does voltmeter P show, and what is the e.m.f. of the cell?

Series and parallel circuits

An electrical heater has a power of $3.0\,\text{kW}$. It is left on for $2\,\text{hours}\,30\,\text{minutes}$. The charge for running the heater for this period is $120\,\text{c}$. What is the price of $1.0\,\text{kWh}$ of electrical energy?

Energy, work and power

In a lighting circuit, the switch is fitted into the live wire. Why is this?

Electrical safety

A wire is positioned in the magnetic field between the poles of a magnet, as illustrated. When current flows through the wire, a force acts on it. Which change would make this force larger?

Forces on a current-carrying conductor

A $12\,\text{V}$ lamp shines at its normal brightness when it is connected to the secondary winding of a mains transformer. The mains voltage is $240\,\text{V}$. The transformer has an efficiency of $100\%$ and the primary winding contains $200$ turns. How many turns does the secondary winding have?

The transformer

Which row indicates the way in which the electrical energy generated by a power station is sent to towns far away?

The transformer

The diagram displays the trace on an oscilloscope screen. The initial peak is produced when a sound pulse is sent out. The later, smaller peak is the echo that returns from a wall. The trace sweeps across the screen in $24\,\text{ms}$. How long does it take the sound to reach the wall?

Sound

The diagram illustrates a nuclear reaction. The shaded particles have no charge. What products are shown in this reaction?

Radioactive decay

The results from the alpha-particle scattering experiment provided evidence for which of the following?

The nuclear model of the atom

What is alpha-radiation emitted by radioactive nuclei made up of?

The three types of emission

A cyclist goes on a journey that lasts $250\,\text{s}$. The graph illustrates how the distance from the starting point changes with time. What is his average speed for the whole journey?

Motion

A nucleus of a uranium isotope contains $238$ nucleons, and $146$ of them are neutrons. Which nucleus represents another isotope of uranium?

The nucleus

An engine is towing a truck along a level track at constant speed. The connection between the engine and the truck fails. The driving force acting on the engine stays constant. What effect does this have on the engine and on the truck?

Balanced and unbalanced forces

What occurs to an object when it is taken to a position where the gravitational field strength is slightly larger?

Mass and weight

Two cylinders P and Q are made from copper. The height of P is double the height of Q. The diameter of P is half that of Q. Which statement is correct?

Density

Which diagram illustrates the addition of the $4.0\,\text{N}$ force and the $3.0\,\text{N}$ force?

Forces

An electric motor connected to the mains is used to raise bricks up to the top of a building. A fuse is fitted in the plug. How could the efficiency of the motor be improved?

Efficiency

An apple drops from a tree. Which row shows the forces acting on the apple and the way the apple moves as it falls?

Balanced and unbalanced forces

Which diagram illustrates the addition of the $4.0\,\text{N}$ force and the $3.0\,\text{N}$ force?

Forces

The diagram shows a geothermal power station. Which useful energy transformation is occurring?

Energy

A motor is employed to raise a load through a vertical distance of $0.50\,\text{m}$, as illustrated. The load has a weight of $40\,\text{N}$. The motor has a power rating of $20\,\text{W}$ and the system operates at $25\%$ efficiency. How long does it take to raise the load?

Energy, work and power

Four different liquids are added to four separate containers. In which container does the liquid exert the largest pressure at the base of the container?

Pressure

A rectangular metal block weighs $6.0\,\text{N}$ and has dimensions of $3.0\,\text{cm} \times 4.0\,\text{cm} \times 5.0\,\text{cm}$. What is the least pressure it can produce when it is placed on a horizontal surface?

Pressure

A piston traps air in a cylinder. The air has pressure $p$, and the air column measures $20\,\text{cm}$ in length. The piston is drawn outwards until the length of the air column has increased by $40\,\text{cm}$. The temperature of the air stays constant. What is the new air pressure?

Particle model

A long tube, completely filled with mercury, is turned upside down in a small dish of mercury. The mercury level inside the tube drops, creating a vacuum at the top. If the atmospheric pressure falls, which length decreases?

Pressure

On a warm day, a cold bottle of drink is set on a table. Water droplets appear on the outside of the bottle. Which process leads to the droplets forming?

Melting, boiling and evaporation

A gas is enclosed in a sealed container. The gas is cooled while the container’s volume is held constant. What happens to the gas molecules?

Particle model

A 100 g sample of lead, initially solid at room temperature, is heated. By 22 s, it has completely melted. The graph plots how the temperature changes with time. The heater has a power of 320 W. Which expression gives the specific latent heat, in J kg$^{-1}$, for the lead?

Melting, boiling and evaporation

The table illustrates how the speeds of four bodies, A, B, C and D, vary with time. Which body has an acceleration that is not constant?

Motion

What rises when a liquid changes into a gas at its boiling point?

Melting, boiling and evaporation

Two liquid-in-glass thermometers are nearly the same. They each have the same amount of the same liquid, and their capillary tubes have equal diameters. The sole distinction is that one thermometer is taller than the other. Which row shows how the ranges and sensitivities of the thermometers compare?

Thermal expansion of solids, liquids and gases

Which statement about a water wave is true?

General properties of waves

The diagram represents a thin converging lens with focal length $f$. At what position should an object be placed so that a real image is formed at the location shown?

Thin lenses

A prism disperses white light. In comparison with blue light, the red light is

Dispersion of light

A student comes across the following statement in her physics book. “Here, the incident angle is more than $42^{\circ}$, the critical angle for glass in air.” What topic is the student reading about?

Refraction of light

Which of the following statements about radio waves is correct?

Electromagnetic spectrum

Ultrasound is employed to chart the ocean floor. In one survey, the water depth is 1200 m. An ultrasound pulse is transmitted from the surface and, when it comes back to the ship, a second pulse is sent straight away. Over any interval of 8.0 s, five pulses are transmitted downwards from the surface. Calculate the speed of the ultrasound in water.

Sound

Which diagram illustrates the magnetic field pattern in the area between the N-poles of the two bar magnets?

Simple magnetism and magnetic fields

Students are required to describe an experiment for determining the resistance of a metallic conductor. Which of the descriptions is correct?

Resistance

An engine is towing a truck along a level track at constant speed. The connection between the engine and the truck fails. The driving force on the engine stays constant. What effect does this have on the engine and on the truck?

Balanced and unbalanced forces

The diagram illustrates three $6.0\,\Omega$ resistors connected so that different total resistances are obtained. What is the difference between the smallest total resistance and the largest total resistance?

Series and parallel circuits

A wire with a length of $0.50\,\text{m}$ and a cross-sectional area of $1.0 \times 10^{-6}\,\text{m}^2$ has resistance $0.75\,\Omega$. A second wire made from the same material has a length of $2.0\,\text{m}$ and a cross-sectional area of $0.50 \times 10^{-6}\,\text{m}^2$. What is the resistance of the longer wire?

Resistance

A defibrillator is a piece of equipment used to deliver an electric shock to a patient’s heart. It delivers an electric shock with energy $240\ \text{J}$ at an average voltage of $2000\ \text{V}$ over $10\ \text{ms}$. What is the average current it supplies?

Electrical current

In a lighting circuit, the switch is fitted into the live wire. Explain why this is done.

Electrical safety

Which cable carries electrical energy at the highest voltage?

Electromotive force and potential difference

A thermistor and a light-dependent resistor are joined in series. Which conditions produce the smallest resistance?

Resistance

An oscilloscope is linked to a d.c. power supply. The time-base on the oscilloscope is turned off. What is observed on the oscilloscope screen?

Uses of an oscilloscope

What is alpha-radiation emitted by radioactive nuclei made up of?

The three types of emission

Which of the following statements about the reactor in a nuclear power station is correct?

Fission and fusion

The alpha-particle scattering experiment provided evidence for which of the following?

The nucleus

Which car has a resultant force acting on it?

Balanced and unbalanced forces

Which statement about two isotopes of the same element is correct?

The nucleus

What apparatus could be used to compare the masses of two objects?

Physical quantities and measurement techniques

The graphs illustrate how a spring’s extension varies with the masses hanging from it, for the spring on planet X and for the spring on planet Y. Which conclusion can be reached from these graphs?

Mass and weight

Cylinders P and Q are both constructed from copper. The height of P is twice that of Q, and the diameter of P is half that of Q. Which statement is correct?

Density

A tennis ball is squeezed. Work is done, so energy is transferred to the air molecules inside the ball and also to the rubber that the ball is made from. Which row is correct?

Elastic deformation

The paths are arranged as illustrated between points X, Y and Z. A person moves along the paths from X to Y to Z, and then returns to X. What are the values of the total displacement and the total distance travelled?

Motion

A girl with mass 35 kg is riding a bicycle, starts from rest and moves downhill in a straight line. She does not pedal. Fig. 1.1 indicates that the slope has a constant gradient.

Motion

Two neutral atoms are atoms of the same element but with different isotopic forms.

Radioactivity

A tiny crack develops in an oil tank and a jet of oil is forced out through the crack. The oil strikes the floor at P, where a puddle of oil begins to spread. Fig. 2.1 shows the oil tank. The gravitational field strength $g$ is $10\,\text{N kg}^{-1}$. The density of the oil is $940\,\text{kg m}^{-3}$ and the crack is $3.3\,\text{m}$ below the oil surface.

Pressure

A student uses the apparatus shown in Fig. 3.1 to produce an extension-load graph for a spring. The loads have known weights. The student hangs increasing loads from the spring and measures the extensions obtained. Fig. 3.2 shows the graph produced. The spring reaches its limit of proportionality at a load of $7.0\,\text{N}$.

Elastic deformation

A rock from space is moving rapidly towards the Earth.

Energy

A nurse is using a mercury-in-glass clinical thermometer to take a patient’s temperature. Fig. 5.1 illustrates the layout of a clinical thermometer.

Thermal expansion of solids, liquids and gases

Fig. 6.1 shows a stationary magnet and a small compass, viewed from above, on a laboratory bench.

Simple magnetism and magnetic fields

A student assembles the circuit in Fig. 7.1. The electromotive force (e.m.f.) of the battery is $6.0\,\text{V}$. Variable resistor X is adjusted to $1.8\,\Omega$.

Electric circuits

A rope is used to haul a bucket of water up from a well. Fig. 8.1 shows the rope coiling onto a cylinder as the handle is rotated. The empty bucket has a mass of $1.0\,\text{kg}$.

Turning effect of forces

Some waves are longitudinal, whereas other waves are transverse.

Refraction of light

Fig. 1.1 depicts a satellite moving at constant speed in a circular orbit around the Earth. The diagram labels a satellite going around the Earth. Fig. 1.1 (not to scale).

Circular motion

In a laboratory at room temperature, a student assembles the circuit shown in Fig. 10.1. The battery has an electromotive force (e.m.f.) of 12 V, and the switch is then closed.

Electric circuits

A sports car is built to remain very stable while taking a corner at high speed. Fig. 2.1 shows where the centre of mass of the car is located. Fig. 2.2 shows a piece of card with an irregular shape.

Centre of gravity

Fig. 3.1 shows a copper kettle with a cylindrical shape holding cold water. It is used to warm the water, and an electric heater is fitted at the bottom.

Thermal expansion of solids, liquids and gases

Several solar panels are fitted on the roof of a house. They take energy from the Sun to produce electricity and also to heat water flowing through tubes within the panels.

Radiation

Two uncharged conducting spheres, K and L, are placed on insulating stands, with Fig. 5.1 showing a positively charged insulating rod positioned beside K.

Electrical charge

In Fig. 6.1, a radiation detector is sitting on a laboratory bench. The detector is turned on, six count-rate readings are taken, and a sample of the radioactive isotope cobalt-60 is positioned close to the detector.

Radioactivity

Fig. 7.1 illustrates the arrangement of a transformer. A lamp is attached to the secondary coil.

Electromagnetic induction

In a cricket game, a player strikes a ball with a bat. The ball then rises straight up, as shown in Fig. 8.1. As it leaves the bat, its speed is $8.7\,\text{m s}^{-1}$. The ball has a mass of $0.16\,\text{kg}$. Fig. 8.2 gives the velocity-time graph for the ball.

Motion

Both sound and ultrasound are waves that can travel through solids, liquids and gases. Fig. 9.1 shows a longitudinal wave with frequency $25\,000\,\text{Hz}$ moving through oil. Fig. 9.2 indicates the centres of the compressions of the sound wave in the liquid.

Sound

A teacher shows convection in a liquid using a glass tube, as in Fig. 1.1. The tube is filled with water and left undisturbed for ten minutes. A purple crystal is then put into the mouth of the tube. This crystal dissolves and makes the water around it turn purple. The tube is then heated gently, as shown in Fig. 1.1.

Convection

A student carries out an experiment using a glass ball and a metal ball. Fig. 2.1 presents the apparatus he uses. The glass ball is put on a cloth-covered bench at the base of a slope. The metal ball is then let go from the top of the slope. It travels down the slope and then collides with the glass ball.

Energy

A student is handed a beaker containing some liquid and is asked to work out the liquid’s density. Density is calculated with the equation $\text{density} = \frac{\text{mass}}{\text{volume}}$. He transfers the liquid into a measuring cylinder. Fig. 3.1 shows the measuring cylinder after the liquid has been poured in.

Density

A student is examining how the resistance of equal-length wires changes when the wires are made from the same material but have different diameters. Resistance is given by the equation $\text{resistance} = \frac{\text{voltage}}{\text{current}}$. The student uses the circuit shown in Fig. 4.1.

Resistance

A student is examining how the current in a thermistor varies with temperature. She assembles the circuit shown in Fig. 1.1. She adds hot water to the beaker. She stirs the water, measures the temperature and checks the ammeter. She enters the temperature and current values in the table in Fig. 1.2. She then repeats the readings at $10\,^{\circ}\text{C}$ intervals while the water cools, until room temperature is reached. She puts all the results into the table, as shown in Fig. 1.2. Fig. 1.3 gives the ammeter reading when the water temperature is $40\,^{\circ}\text{C}$.

Electrical current

A student determines the focal length of a convex lens. He assembles the apparatus shown in Fig. 2.1. He positions the lens some distance from the illuminated object. He slides the screen until a clear image of the object is formed on the screen.

Thin lenses

A student and her friend obtain an approximate value for the speed of sound in air by using echoes. She positions herself a long way from a wall that reflects sound. She claps at a steady rate. She then alters her clapping rate until each clap matches the echo from the previous clap. Her friend uses a stopwatch to find the time $t$ between claps. They measure how far the wall is away. The time $t$ between claps is measured four times. The values of $t$, in seconds, are listed below. $0.87 \quad 0.97 \quad 0.94 \quad 0.88$

Sound

A student maps the pattern of the magnetic field between the North poles of two bar magnets using a plotting compass. The student sets the magnets on a sheet of white paper, as shown in Fig. 4.1.

Simple magnetism and magnetic fields