Oct/Nov 2017

Which set includes only scalar quantities?

Physical quantities and measurement techniques

A car covers a distance of $200\,\text{m}$ in $20\,\text{s}$. The car's engine exerts a driving force of $1000\,\text{N}$. What power output is produced by the engine?

Power

A gas is warmed in a sealed container at fixed volume. What occurs to the molecules of the gas?

Particle model

Scientists think that some lakes are becoming smaller because of evaporation. What makes the rate of evaporation increase?

Melting, boiling and evaporation

A sample of solid wax is heated until it melts in a boiling tube and then left to cool down. The graph shows the cooling curve. What is happening between points X and Y?

Melting, boiling and evaporation

When a substance boils or melts, it either absorbs energy or releases energy. Which row shows the energy transfer for the change of state?

Melting, boiling and evaporation

A $50\,\text{g}$ block of metal has its temperature increased by $40\,^{\circ}\text{C}$. The metal’s specific heat capacity is $0.40\,\text{J g}^{-1}\,^{\circ}\text{C}^{-1}$. What amount of thermal energy is transferred?

Specific heat capacity

In which substance is thermal energy conduction mainly caused by the motion of electrons?

Conduction

Four similar metal plates are placed at equal distances from a heater that gives out infra-red radiation. The plates are coated dull black, dull white, shiny black and shiny white. Which plate absorbs the greatest amount of radiation and which plate reflects the greatest amount of radiation?

Radiation

A wave moves through water in a glass-sided tank. The diagram gives a side-on view of the wave at one moment. What are the amplitude and the wavelength of the wave?

General properties of waves

An earthquake wave moves across the Earth’s solid surface from east to west. The solid surface oscillates in a north-south direction. How can the earthquake wave be described?

General properties of waves

A manufacturer checks the three dimensions of a wooden floor tile with three separate instruments. The tile’s approximate measurements are shown as follows: length $0.4\,\text{m}$, width $0.08\,\text{m}$, thickness $0.005\,\text{m}$. (not to scale) Which instruments would be used to measure each of these dimensions accurately?

Physical quantities and measurement techniques

A solid plastic cylinder is placed in a liquid with refractive index $1.4$. Light in the plastic cylinder meets the inner surface at an angle of incidence of $70^{\circ}$. Total internal reflection occurs. What are the values of the critical angle in the plastic and the refractive index of the plastic?

Refraction of light

What is the lens called, and what shape does it have, for correcting short sight?

Thin lenses

An object is positioned before a converging lens. The lens produces a magnified image of the object on a screen. Which statement is correct?

Thin lenses

A form of electromagnetic radiation has these characteristics: It has ionising properties. Its frequency is greater than the frequency of microwaves. It cannot be detected by the human eye. What is this radiation?

Electromagnetic spectrum

Which row shows the speed of sound in air, in water and in steel?

Sound

When a sound wave moves from one medium into another, its wavelength becomes longer. What happens to the frequency and the speed of the sound?

Sound

The diagram illustrates the pattern and direction of the magnetic field between two magnetic poles X and Y. Which pole types are X and Y?

Simple magnetism and magnetic fields

The diagram shows a sensitive device enclosed by a shield that stops the magnetic field from reaching the device. In what way does the shield protect the device?

Simple magnetism and magnetic fields

A polythene rod becomes charged when it is rubbed with a cloth. Which statement explains the reason the cloth becomes charged?

Electrical charge

What does electromotive force (e.m.f.) mean?

Electromotive force and potential difference

The speed-time graph shows a brief journey. Which distance-time graph shows that same journey?

Motion

In a circuit, a voltmeter is used to measure the potential difference across a lamp, while an ammeter is used to measure the current in the lamp. Which diagram shows the circuit?

Circuit diagrams and circuit components

A battery in a circuit has two identical cells arranged in parallel. Which row states how currents $I_1$ and $I_2$ are related and gives the electromotive force (e.m.f.) of the battery?

Electromotive force and potential difference

The diagram illustrates the circuit for a hair-dryer. The fan motor is rated at $0.10\,\text{kW}$ and each heater is rated at $0.40\,\text{kW}$. Electricity costs $8.0\,\text{cents/kW h}$. What is the cost of operating the hair-dryer for two hours when switches P and Q are closed and switch R is open?

Uses of electricity

What is the reason that the metal casings of electrical appliances are earthed?

Electrical safety

The diagram illustrates a wire XY positioned between the poles of a magnet. Each end of the wire is attached to a sensitive ammeter. The wire is then moved, and a reading is recorded. In what direction is the wire moved?

Electromagnetic induction

What particles are given off by a hot metal filament?

Electrical charge

A light-emitting diode (LED) is linked to an alternating current (a.c.) supply. The LED switches on and off repeatedly. In which direction is the current in the LED when it is producing light?

Action and use of circuit components

A thin beam of alpha-particles is directed at a very thin sheet of gold foil. In which direction do the greatest number of alpha-particles finally travel?

The nuclear model of the atom

A nucleus of phosphorus $^{32}_{15}\text{P}$ emits a beta-particle and changes into a different nucleus. What are the nucleon number and the proton number of the new nucleus?

The three types of emission

In what way is a nucleus of the isotope chlorine-37 different from a nucleus of the isotope chlorine-35?

The nucleus

An object moves at a constant speed of $10\,\text{m s}^{-1}$ for $20\,\text{s}$. Over the following $10\,\text{s}$, it accelerates uniformly until its speed reaches $20\,\text{m s}^{-1}$. What is the total distance covered by the object in the $30\,\text{s}$?

Motion

What types of radiation can be emitted during radioactive decay?

The three types of emission

A skydiver is descending at terminal velocity. He then deploys his parachute. Which row shows the direction of the resultant force acting on the skydiver and the direction of the skydiver’s acceleration immediately after the parachute deploys?

Balanced and unbalanced forces

The diagram shows two objects placed on a beam balance. The beam balance is in equilibrium. Which quantities could be different?

Mass and weight

A metal wire hangs from a support, and loads with different masses are hung from its lower end. The table shows how the extension of the wire changes with the mass of the load. Between which values of mass does the limit of proportionality lie?

Elastic deformation

The diagram illustrates a mercury manometer attached to a container of gas. Mercury has a density of $14\,000\,\text{kg m}^{-3}$. The gravitational field strength $g$ is $10\,\text{N kg}^{-1}$. What pressure difference exists between the gas in the container and the atmosphere?

Pressure

An astronaut on the Moon lets go of a tool box with mass $3.0\,\text{kg}$. It starts from rest, and when it strikes the surface its kinetic energy is $0.96\,\text{J}$. With what speed does the tool box strike the Moon’s surface?

Energy

Which list includes only scalar quantities?

Physical quantities and measurement techniques

The diagram depicts a mercury manometer attached to a gas container. Mercury has a density of $14\,000\,\text{kg m}^{-3}$. The gravitational field strength $g$ is $10\,\text{N kg}^{-1}$. What is the pressure difference between the gas in the container and the atmosphere?

Pressure

A gas syringe holds a constant mass of air. The air has a volume of $240\,\text{cm}^3$ and a pressure of $5.0 \times 10^4\,\text{Pa}$. The air is then compressed slowly while the temperature is kept unchanged, until the pressure becomes $1.5 \times 10^5\,\text{Pa}$. What is the air’s final volume?

Kinetic particle model of matter

A liquid needs an extremely large rise in pressure to be compressed, whereas a gas can be compressed with a much smaller rise in pressure. Which statement explains this?

Particle model

A container of liquid is left on a laboratory bench. Part of the liquid evaporates. What occurs, and what is the reason for it?

Melting, boiling and evaporation

Solid wax is heated until it melts in a boiling tube and is then left to cool down. The graph shows the cooling curve. What is taking place between points $X$ and $Y$?

Melting, boiling and evaporation

What does the term heat capacity of a solid object mean?

Specific heat capacity

In a liquid-in-glass thermometer, the separation between the ice point and the steam point is $20\,\text{cm}$. The upper end of the liquid column is $12\,\text{cm}$ above the ice point. What is the temperature?

Thermal expansion of solids, liquids and gases

A thermocouple is a kind of thermometer. Which statement is correct for a thermocouple?

Physical quantities and measurement techniques

A heater is intended to emit thermal energy by radiation. Which design modification would reduce the thermal energy released by radiation?

Radiation

A sound wave in a solid is shown as a sequence of lines. The diagram indicates compressions $C$ and rarefactions $R$ at a particular moment. Which statement is correct?

Sound

A manufacturer checks the three dimensions of a wooden floor tile with three separate instruments. The tile’s approximate measurements are shown as: length $0.4\,\text{m}$, width $0.08\,\text{m}$ and thickness $0.005\,\text{m}$. Which instruments are used to measure each of these dimensions accurately?

Physical quantities and measurement techniques

Which diagram illustrates reflection from a plane mirror?

Reflection of light

A beam of light is incident on a plastic block of refractive index $1.5$. The angle of incidence is $50^\circ$. What is the angle of refraction?

Refraction of light

A solid plastic cylinder is placed in a liquid with refractive index $1.4$. Light travelling in the plastic cylinder hits the inside surface at an angle of incidence of $70^\circ$. The light undergoes total internal reflection. Find the value of the critical angle in the plastic and the refractive index of the plastic.

Refraction of light

The ray diagrams, X and Y, illustrate two ways a thin converging lens can create an image larger than its object. Which devices use a lens arranged as in diagram X and as in diagram Y?

Thin lenses

The diagram presents the electromagnetic spectrum and names three components. The spectrum is arranged from longer wavelength to shorter wavelength. Which component of the spectrum is used in a sunbed to create a suntan?

Electromagnetic spectrum

Which row shows the speed of sound in air, in water and in steel?

Sound

A compass needle is moved to several different positions around a strong bar magnet. At which position is the compass needle’s direction shown incorrectly?

Simple magnetism and magnetic fields

A plastic block is rubbed using a silk handkerchief, and the block then becomes charged. What makes the block become charged?

Electrical charge

A rod with a negative charge is held close to a neutral metal sphere placed on an insulating stand. Which diagram shows how the charge is distributed on the sphere?

Electrical charge

A $6.0\,\text{V}$ battery, three resistors, and three voltmeters are arranged in the circuit diagram shown. Voltmeter 1 shows $2.0\,\text{V}$. What are the readings on voltmeter 2 and voltmeter 3?

Electromotive force and potential difference

The speed-time graph shows a brief journey. Which distance-time graph shows the same journey?

Motion

One length of wire has a resistance of $16\,\Omega$. It measures $20\,\text{cm}$ in length and has a cross-sectional area of $2.0\,\text{mm}^2$. Which wire, made from the same material, would have a resistance of $8.0\,\Omega$?

Resistance

A circuit battery is made up of two identical cells arranged in parallel. Which row states the connection between currents $I_1$ and $I_2$ and gives the electromotive force (e.m.f.) of the battery?

Electromotive force and potential difference

The diagram illustrates the circuit of a hair-dryer. The fan motor is rated at $0.10\,\text{kW}$ and each heater is rated at $0.40\,\text{kW}$. The price of electricity is $8.0\,\text{cents/kW h}$. How much does it cost to operate the hair-dryer for two hours when switches $P$ and $Q$ are closed and switch $R$ is open?

Uses of electricity

Why is the coil in an electric motor wrapped around a soft-iron cylinder?

Magnetic effect of a current

A straight wire carries a current into the paper. The diagram shows three magnetic field lines surrounding the wire. The current in the wire increases. What is the direction of the field lines, and what change happens to the field lines as the current increases?

Magnetic effect of a current

What particles are given off by a hot metal filament?

Electrical charge

A circuit contains a thermistor and a light-dependent resistor (LDR). The resistance of the thermistor and the resistance of the LDR both rise. What alteration would produce this?

Action and use of circuit components

A sample includes atoms of an isotope whose half-life is $7.2\,\text{years}$. Which quantity is reduced by half every $7.2\,\text{years}$?

Half-life

A beam made up of alpha-particles $(\alpha)$, beta-particles $(\beta)$, and gamma rays $(\gamma)$ enters a magnetic field. Which diagram represents the paths of these particles in the magnetic field?

The three types of emission

A thin sheet of gold foil is bombarded with a narrow beam of alpha-particles. In which direction do the greatest number of alpha-particles travel after this?

The nuclear model of the atom

A skydiver in free fall leaps from an aircraft. While he is falling, an upward force and a downward force act on his body, producing a resultant force. Before terminal velocity is reached, how do the magnitudes of the forces change?

Balanced and unbalanced forces

A phosphorus nucleus $^{{32}}_{{15}}\text{P}$ releases a beta-particle, producing a different nucleus. What are the nucleon number and the proton number of the resulting nucleus?

The three types of emission

The diagram depicts two objects placed on a beam balance. The beam balance is balanced in equilibrium. Which quantities could be different?

Mass and weight

Two blocks are connected together. One block has a density of $6.0\,\text{g cm}^{-3}$, while the other has a density of $9.0\,\text{g cm}^{-3}$. What is the combined density of the two blocks when they are joined together?

Density

A diver weighing $500\,\text{N}$ is standing at the far end of a springboard that is $2.0\,\text{m}$ long and fixed at point $P$. The springboard itself weighs $500\,\text{N}$. Its centre of mass is located at the midpoint of the board. What is the total moment about point $P$ due to the diver and the board?

Turning effect of forces

A tennis ball with mass $56\,\text{g}$ is moving at $1500\,\text{metres per minute}$. Which expression is equivalent to the kinetic energy, in joules, of the tennis ball?

Energy

At a hydroelectric power station, $4.2 \times 10^5\,\text{kg}$ of water flows through the turbines each second. The turbines are positioned $50\,\text{m}$ below the surface of the reservoir. Take the gravitational field strength $g$ as $10\,\text{N kg}^{-1}$. If there are no energy losses, what is the power output of the power station?

Power

Fig. 1.1 illustrates a painter standing on a wooden plank, positioned directly above the support on the right. The plank measures 3.6 m in length, 0.35 m in width and 0.025 m in thickness. The gravitational field strength $g$ is $10\,\text{N kg}^{-1}$ and the plank has a mass of 23 kg.

Turning effect of forces

Fig. 10.1 shows the electromagnetic spectrum.

Electromagnetic spectrum

Fig. 11.1 shows a negatively charged rod positioned near an uncharged metal sphere mounted on an insulating stand.

Series and parallel circuits

Fig. 2.1 depicts a can of compressed air being used to remove dust from a computer keyboard.

Pressure

Old gold jewellery is heated in a furnace until it melts. Fig. 3.1 shows the molten gold being poured into a mould so that a gold bar is formed. The melting point of gold is $1100\,^{\circ}\text{C}$.

Melting, boiling and evaporation

Fig. 4.1 illustrates a mercury-in-glass thermometer constructed with a glass capillary tube.

Thermal expansion of solids, liquids and gases

Some medical procedures make use of ultrasound.

Sound

The glass tube makes up the main body of a cathode-ray oscilloscope. Electrons are released from a hot metal filament at one end of the tube.

Electric circuits

An electric circuit is made up of a battery, a variable resistor and connecting wires. The sections PQ and QR of the connecting wire lie in a part of space with a uniform magnetic field. In Fig. 7.1, the shaded region shows the magnetic field.

Forces on a current-carrying conductor

A sample of the radioactive isotope radon-222 undergoes decay by emitting alpha-particles.

Radioactivity

Fig. 9.1 displays a large container ship moving in a straight line at constant speed. The resistive force on the ship is $2.8 \times 10^{6}\,\text{N}$.

Energy, work and power

Seen from above, two small tugboats are towing a large ship in a harbour. Fig. 1.1 gives the directions of the forces acting on the ship. Fig. 1.1 (not to scale) shows a ship being towed by two tugboats. Each tugboat applies a force of 49 kN to the ship. The forces are placed symmetrically at angles of 20^{\circ} above and 20^{\circ} below the centre line of the ship.

Balanced and unbalanced forces

A boiler that contains water is connected to a 230 V mains supply, and the heater inside the boiler is running at full power.

Specific heat capacity

The metals listed below are used in many different applications. aluminium copper iron silver steel

Electromagnetic induction

When a force acts on a solid object, it can accelerate, causing its velocity to change.

Elastic deformation

A horizontal solid rectangular concrete block is resting on level ground, with one of its largest faces touching the ground. Fig. 3.1 gives the block’s dimensions. The block has a weight of 240 N.

Pressure

A filament lamp rated at 75 W in an office is mistakenly left on for 63 hours while the office is shut.

Energy, work and power

A process known as nuclear fusion occurs in the Sun.

The Sun as a star

Fig. 6.1 depicts a girl positioned a few hundred metres ahead of a large building. She operates a signal generator together with a loudspeaker to produce a brief pulse of sound directed at the building. The sound frequency is 3700 Hz. After a short interval, the girl hears an echo.

Sound

A circuit containing an ammeter, a light-dependent resistor (LDR) and a 1800 Ω fixed resistor is powered by a 4.5 V battery. Fig. 7.1 shows the circuit diagram.

Series and parallel circuits

Inside a car’s engine compartment, the battery delivers a current of 120 A to the starter motor.

Electrical current

Fig. 9.1 depicts an astronaut in space close to a space station orbiting above the Earth. The astronaut plus all of his equipment has a total mass of 160 kg. At first the astronaut is stationary relative to the space station, then the rope pulls him towards the space station. His acceleration towards the space station is $0.35\,\text{m s}^{-2}$ for 1.2 s.

Forces

A student uses a top-pan balance to determine the mass of a table-tennis ball, as illustrated in Fig. 1.1. The balance is calibrated to the nearest gram.

Physical quantities and measurement techniques

A student carries out an investigation into how high a table-tennis ball rebounds. He releases the ball from a height of $60\,\text{cm}$ onto a tiled floor, as shown in Fig. 2.1. He measures the bounce height $h$ using a metre rule with millimetre divisions.

Physical quantities and measurement techniques

Fig. 3.1 illustrates a thermistor. A thermistor is a resistor whose resistance varies with temperature changes. Fig. 3.2 illustrates a circuit that has only been partly completed.

Circuit diagrams and circuit components

In Fig. 4.1, AB is a converging lens. The object PQ is positioned so that end Q lies on the principal axis ST of the lens.

Thin lenses

A student is examining the period of a simple pendulum. The period $T$ is the time for one full oscillation of the pendulum. She arranges the pendulum so that the point of support is at a constant height above the bench surface. During the investigation, she leaves this height unchanged and does not move the clamp. Fig. 1.1 shows a scale drawing of her apparatus.

Motion

A student is examining how insulation affects the cooling rate of hot water in a beaker. He pours $250\text{ cm}^3$ of hot water into a beaker and inserts a thermometer into the water, as shown in Fig. 2.1. He waits for a brief period. He then starts a stopwatch as he measures the temperature $\theta$ of the hot water. This is at time $t = 0$. Fig. 2.2 shows the thermometer at $t = 0$.

Transfer of thermal energy

A student finds the refractive index of the material of a transparent block ABCD by following the route of a light ray through it. The setup is illustrated in Fig. 3.1.

Refraction of light

A student is examining how the resistance of a wire changes as its length changes. He uses the equation $R = \frac{V}{I}$. The equipment provided is: power supply, ammeter, voltmeter, switch, connecting leads and crocodile clips, a length of resistance wire, metre rule, wire cutters. Write a plan for the investigation.

Resistance