AS & A Level Physics - 9702 Paper 1 2019 Summer Zone 2

What is equivalent to 2000 microvolts?

What is the number of SI base units required to express electric field strength and power?
[Table_1]

The Planck constant $h$ has SI units J·s. Which equation could be used to calculate the Planck constant?

Two cables are attached to a bracket and exert forces as shown.

What are the magnitudes of the horizontal and vertical components of the resultant of the two forces?

A student wishes to determine the density $\rho$ of lead. She measures the mass and diameter of a small sphere of lead:
mass = (0.506 ± 0.005) g
diameter = (2.20 ± 0.02) mm.
What is the best estimate of the percentage uncertainty in her calculated value of $\rho$?

Two quantities $p$ and $q$ are directly proportional to each other.
Experimental results are taken and plotted in a graph of $q$ against $p$.
Which graph shows there were random errors in the measurements of $p$ and $q$?

A man of mass 75.2 kg uses a set of weighing scales to measure his mass three times. He obtains the following readings.

[Table_1]

Which statement best describes the precision and accuracy of the weighing scales?

The graph shows how a physical quantity varies with time.

Which event could best be represented by the graph? 

What describes the mass of an object?

A car has mass $m$. A person needs to push the car with force $F$ in order to give the car acceleration $a$. The person needs to push the car with force $2F$ in order to give the car acceleration $3a$.

Which expression gives the constant resistive force opposing the motion of the car?

Two bar magnets P and Q are mounted on floats which can slide without friction along an air track.

The two magnets slide towards each other along the air track and interact, without making contact.

The relative speed of approach of the magnets is equal to their relative speed of separation.

Which statement about P and Q must be correct? 

A submarine descends vertically at constant velocity. The three forces acting on the submarine are viscous drag, upthrust and weight.

Which relationship between their magnitudes is correct?

A small positive charge can move inside a uniform electric field.

The charge moves along different straight paths between points P, Q, R and S.

Which row gives two paths that result in the same total work done on the charge? 

A car of mass $m$ travels at constant speed up a slope at an angle $\theta$ to the horizontal, as shown in the diagram. Air resistance and friction provide a resistive force $F$. The acceleration of free fall is $g$.

What is the force needed to propel the car at this constant speed? 

A volume of $1.5 \, \text{m}^3$ of water is mixed with $0.50 \, \text{m}^3$ of alcohol. The density of water is $1000 \, \text{kg} \, \text{m}^{-3}$ and the density of alcohol is $800 \, \text{kg} \, \text{m}^{-3}$.

The volume of the mixture is $2.0 \, \text{m}^3$.

What is the density of the mixture?

A parachutist is falling at constant (terminal) velocity.

Which statement is not correct?

A combined heat and power (CHP) station generates electrical power and useful heat. The diagram shows the input and output powers for a CHP station.

What is the efficiency of the CHP station for producing useful power? 

A bungee jumper jumps off a high bridge, when attached to it by a long elastic rope which obeys Hooke's law.

The gravitational potential energy of the jumper is measured relative to the lowest point reached by the jumper.

Which graph shows the variation of the gravitational potential energy of the jumper, and the elastic potential energy in the rope, with the vertical distance fallen from the top of the bridge?

A train on a mountain railway is carrying 200 people of average mass 70$\, \text{kg}$ up a slope at an angle of $30^{\circ}$ to the horizontal and at a speed of $6.0\, \text{m s}^{-1}$. The train itself has a mass of $80\,000\, \text{kg}$. The percentage of the power from the engine which is used to raise the passengers and the train is $40\%$

What is the power of the engine?

A wire X is stretched by a force and gains elastic potential energy $E$.

The same force is applied to wire Y of the same material, with the same initial length but twice the diameter of wire X. Both wires obey Hooke's law.

What is the gain in elastic potential energy of wire Y?

The diagram shows the arrangement of atoms in a particular crystal.

Each atom is at the corner of a cube.

The mass of each atom is $3.5 \times 10^{-25} \text{ kg}$. The density of the crystal is $9.2 \times 10^{3} \text{ kg m}^{-3}$.

What is the shortest distance between the centres of two adjacent atoms? 

The stress-strain graphs for loading and unloading four different materials are shown.

Which material exhibits purely elastic behaviour?

The diagram illustrates the position of particles in a progressive sound wave at one instant in time.

The speed of the wave is \( v \). P and Q are two points in the wave a distance \( L \) apart.

What is an expression for the frequency of the wave?

A wave moves along the surface of water.

The diagram shows the variation of displacement $s$ with distance along the wave at time $t = 0$.

Which graph best shows the variation with time $t$ of the displacement $s$ of the point $P$ on the wave? 

In an experiment to determine the wavelength of sound in air, a stationary wave is set up in an air column.

The distance between a node and an adjacent antinode is $L$.

What is the wavelength of the sound?

In one of the first experiments to demonstrate the Doppler effect, a train was filled with trumpeters all playing a note of frequency 440 Hz. The difference in observed frequency of the note as the train directly approached a stationary observer was 22 Hz. The speed of sound was 340 m s$^{-1}$.

At which speed was the train moving?

The electromagnetic spectrum consists of waves with different wavelengths.

Which row correctly identifies regions of the electromagnetic spectrum?

A cathode-ray oscilloscope (CRO) is used to display the trace from a sound wave. The time-base is set at $5 \, \mu \text{s} \, \text{mm}^{-1}$.

What is the frequency of the sound wave?

Monochromatic light is directed at a diffraction grating, as shown.

Which diagram could show all the possible directions of the light, after passing through the grating, that give maximum intensity? 

Why can an observable interference pattern never be obtained between two monochromatic beams of light from different lamps?

A student sets up apparatus to observe the double-slit interference of monochromatic light, as shown.

Interference fringes are formed on the screen.

Which change would increase the distance between adjacent fringes?

An electron is situated in a vacuum between two charged plates, as shown.

Which statement describes the motion of the electron due to the uniform electric field?

A length of wire is connected into a circuit.
The area of the cross-section of the wire changes from $A$ at $R$ to $\frac{1}{2}A$ at $S$.
There is a constant current in the wire. Charge $Q$ passes $R$ in time $t$.
What is the charge passing point $S$ in the same time $t$?

Four wires are made of the same metal. The cross-sectional areas, lengths and thermodynamic temperatures of the wires are shown.
Which wire has the largest resistance?
[Table: cross-sectional area, length, temperature]
A | A | 2L | 2T
B | A | L | T
C | 2A | 2L | 2T
D | 2A | L | T

A cell with internal resistance is connected to a variable resistor R as shown.

The resistance of R is gradually decreased.
How do the current $I$ and the terminal potential difference across the cell change?

Kirchhoff's first law states that the sum of the currents entering a junction in a circuit is equal to the sum of the currents leaving it. The law is based on the conservation of a physical quantity. What is this physical quantity?

A circuit contains two batteries, each of negligible internal resistance, and two resistors as shown.
The galvanometer has a current reading of zero.
What is the electromotive force (e.m.f.) of battery X?

A nucleus of francium-221 ($^{221}_{87}\text{Fr}$) decays into a nucleus of bismuth-209 ($^{209}_{83}\text{Bi}$) in several steps. Which particles could be emitted?

Which equation describes the changes to the quark composition of a nucleus and the lepton emission during the process of $\beta^+$ decay?

There are protons, neutrons and electrons in the simple model of an atom. To which class (group), hadron or lepton, do these particles belong? [Table_1]