All Questions: AS & A Level Physics - 9702 Paper 2 2018 Summer Zone 3
Theory
MCQ
01.
Theory 8 Marks
CH2 - MEASUREMENT TECHNIQUES

(a) An analogue voltmeter is used to take measurements of a constant potential difference across a resistor.

For these measurements, describe one example of

(i) a systematic error, [1]

(ii) a random error. [1]

(b) The potential difference across a resistor is measured as 5.0 V ± 0.1 V. The resistor is labelled as having a resistance of 125Ω ± 3%.

(i) Calculate the power dissipated by the resistor. [2]

(ii) Calculate the percentage uncertainty in the calculated power. [2]

(iii) Determine the value of the power, with its absolute uncertainty, to an appropriate number of significant figures. [2]

02.
Theory 11 Marks
CH5 - FORCES, DENSITY & PRESSURE, CH6 - WORK, ENERGY & POWER, CH14 - WAVES

(a) State what is meant by $\textit{work done}$.  [1]

(b) A diver releases a solid sphere of radius 16 cm from the sea bed. The sphere moves vertically upwards towards the surface of the sea. The weight of the sphere is 20 N. The upthrust acting on the sphere is 170 N. The upthrust remains constant as the sphere moves upwards.

(i) Calculate the density of the material of the sphere.   [2]

(ii) Briefly explain the origin of the upthrust acting on the sphere.  [1]

(iii) Calculate the acceleration of the sphere as it is released from rest.  [2]

(iv) The viscous (drag) force \(D\) acting on the sphere is given by

$$D = kr^{2}v^{2}$$

where \(r\) is the radius of the sphere and \(v\) is its speed. The constant \(k\) is equal to 810 kg m$^{-3}$.

Determine the constant (terminal) speed reached by the sphere.  [3]

(v) The diver releases a different sphere that moves with a constant speed of 6.30 m s$^{-1}$ directly towards a stationary ship. The sphere emits sound of frequency 4850 Hz. The ship detects sound of frequency 4870 Hz as the sphere moves towards it. Determine, to three significant figures, the speed of the sound in the water. [2]

03.
Theory 12 Marks
CH3 - KINEMATICS, CH4 - DYNAMICS, CH6 - WORK, ENERGY & POWER

A ball is thrown vertically upwards towards a ceiling and then rebounds, as illustrated in Fig. 3.1.

The ball is thrown with speed 9.6 m s$^{-1}$ and takes a time of 0.37 s to reach the ceiling. The ball is then in contact with the ceiling for a further time of 0.085 s until leaving it with a speed of 3.8 m s$^{-1}$. The mass of the ball is 0.056 kg. Assume that air resistance is negligible.

(a) Show that the ball reaches the ceiling with a speed of 6.0 m s$^{-1}$. [1]

(b) Calculate the height of the ceiling above the point from which the ball was thrown. [1]

(c) Calculate

(i) the increase in gravitational potential energy of the ball for its movement from its initial position to the ceiling, [2]

(ii) the decrease in kinetic energy of the ball while it is in contact with the ceiling. [2]

(d) State how Newton's third law applies to the collision between the ball and the ceiling. [2]

(e) Calculate the change in momentum of the ball during the collision.  [2]

(f) Determine the magnitude of the average force exerted by the ceiling on the ball during the collision. [2]

04.
Theory 8 Marks
CH9 - DEFORMATION OF SOLIDS

(a) Define the Young modulus of a material.   [1]

(b) A metal rod is compressed, as shown in Fig. 4.1.

The variation with compressive force $F$ of the length $L$ of the rod is shown in Fig. 4.2.

Use Fig. 4.2 to

(i) determine the spring constant $k$ of the rod,   [2]

(ii) determine the strain energy stored in the rod for $F = 90\text{kN}$.   [3]

(c) The rod in (b) has cross-sectional area $A$ and is made of metal of Young modulus $E$. It is now replaced by a new rod of the same original length. The new rod has cross-sectional area $A/3$ and is made of metal of Young modulus $2E$. The compression of the new rod obeys Hooke's law.

On Fig. 4.2, sketch the variation with $F$ of the length $L$ for the new rod from $F = 0$ to $F = 90\text{kN}$. [2]

05.
Theory 8 Marks
CH14 - WAVES, CH15 - SUPERPOSITION

(a) State the relationship between the intensity and the amplitude of a wave.   [1]

(b) Microwaves of the same amplitude and wavelength are emitted in phase from two sources P and Q. The sources are arranged as shown in Fig. 5.1.

A microwave detector is moved along a path that is parallel to the line joining P and Q. A series of intensity maxima and intensity minima are detected.

When the detector is at a point X, the distance PX is 1.840 m and the distance QX is 2.020 m. The microwaves have a wavelength of 6.0 cm.

(i) Calculate the frequency of the microwaves.   [2]

(ii) Describe and explain the intensity of the microwaves detected at X.    [3]

(iii) Describe the effect on the interference pattern along the path of the detector due to each of the following separate changes.   [2]

  1. The wavelength of the microwaves decreases.
  2. The phase difference between the microwaves emitted from the sources changes to 180°.

06.
Theory 8 Marks
CH19 - CURRENT OF ELECTRICITY, CH20 - D.C. CIRCUITS

A wire X has a constant resistance per unit length of 3.0 \Omega \text{m}^{-1} and a diameter of 0.48 \text{mm}.
(a) Calculate the resistivity of the metal of wire X.
resistivity = \text{..................................................} \Omega \text{m} [3]
(b) The wire X is connected into the circuit shown in Fig. 6.1.

The battery has an electromotive force (e.m.f.) of 5.0 V and an internal resistance of 2.0 \Omega. The wire X and a resistor R of resistance 4.5 \Omega are connected in parallel. The current in the battery is 1.6 A.
(i) Calculate the potential difference across resistor R.
potential difference = \text{..................................................} V [1]
(ii) Determine, for wire X,
1. its resistance,
resistance = \text{..................................................} \Omega [3]
2. its length.
length = \text{..................................................} \text{m} [1]

07.
Theory 4 Marks
CH26 - PARTICLE & NUCLEAR PHYSICS

A graph of nucleon number A against proton number Z is shown in Fig. 7.1.



The graph shows a cross (labelled P) that represents a nucleus P.

Nucleus P decays by emitting an \(\alpha\) particle to form a nucleus Q.
Nucleus Q then decays by emitting a \(\beta^-\) particle to form a nucleus R.

(a) On Fig. 7.1, use a cross to represent

(i) nucleus Q (label this cross Q), [1]

(ii) nucleus R (label this cross R). [1]

(b) State the name of the class (group) of particles that includes the \(\beta^-\) particle.
........................................................................................................................ [1]

(c) The quark composition of one nucleon in Q is changed during the emission of the \(\beta^-\) particle.
Describe this change to the quark composition.
........................................................................................................................
........................................................................................................................ [1]