Practice Paper 2 (Edexcel IAL Physics)

A person is pushing a trolley at a constant velocity.

The floor exerts a force P on the person, the person exerts a force Q on the trolley.

The trolley exerts a force R on the person and the total drag force on the trolley is S.

Which pair of forces is a Newton's Third Law pair?

A beam is balanced on two supports as shown.

The beam has a weight *W *and the reaction forces at the two supports are P and Q.

Which of the following statements about the magnitudes of the forces is correct?

A block of wood is stationary on a frictionless ramp as shown.

The block is held in place by a string. The weight of the block is $W$. The force applied to the block by the string is $F$.

A triangle of forces can be used to determine the magnitude and direction of the normal contact force $N$ acting on the block.

Which of the following triangles is correct?

Two different springs, $S_{1}$ and $S_{2}$, are suspended from a fixed support. Masses are attached to the bottom of $S_{1}$ and $S_{2}$ as shown.

The extension of $S_{1}$ is $x$, and the extension of $S_{2}$ is $\frac{x}{3}$. The elastic strain energy in spring $S_{1}$ is $E$.

Which of the following is the elastic strain energy in spring $S_{2}$?

An electric motor lifts a load of weight $50\text{N}$ through a vertical height of $1 . 5 \text{m}$ in $4.0\text{s}$. The motor is connected to a $12\text{V}$ supply and draws a current of $2.0\text{A}$.

Which of the following expressions gives the efficiency of the motor, as a percentage?

A student investigated the viscosity of olive oil at different temperatures using a steel sphere of radius $r$.

Describe how the student can make measurements of the steel sphere to determine its radius accurately.

Explain how the student can ensure that Stokes' law will apply to the steel sphere as it falls through the olive oil.

The student dropped the steel sphere into a tall cylinder of olive oil, as shown, and timed the sphere as it fell through the oil at terminal velocity.

The student placed two rubber bands around the cylinder and started a stopwatch when the sphere passed the first band and stopped it when the sphere passed the second band.

The student recorded the time $t$ for the ball to fall through a distance of $21.0\text{cm}$ and repeated this for three different temperatures. They calculated the viscosity $η$ at each temperature using the formula

$\\eta = \frac{2 r^{2} g ( \rho_{s} - \rho_{o} )}{9 v}$

radius of steel sphere $r=2.2\text{mm}$ density of steel $ρ_{s} = 7800 \text{kg m}^{-3}$ density of olive oil at 20 °C $ρ_{o} = 920 \text{kg m}^{-3}$

Their results are shown in the table.

The student concluded that the viscosity of olive oil decreases linearly with temperature.

Criticise the student's investigation and conclusion.

*A large spacecraft is made up of several ‘stages’. Each stage consists of a rocket motor and a fuel tank. Once a stage has used all its fuel, the rocket motor in that stage shuts down. The stage then disconnects from the spacecraft and falls back to Earth.

As the rocket is rising due to the upward force of the first stage, an astronaut feels himself pushed further and further back, compressing the back of his seat.

When the first stage shuts down, the astronaut is suddenly projected forwards by the seat. The astronaut is held in place by a safety strap.

Explain the effects experienced by the astronaut. You may assume that the force provided by the first stage rocket motor is constant until the moment it shuts down.

A student used a force meter attached to one end of a uniform metre rule to determine the mass of a block. The centre of the metre rule is attached to a stand about which it can pivot.

A block of unknown mass $m$ can be attached to the metre rule through one of the small holes, as shown.

The student attached the block to each small hole and adjusted the force meter to make it vertical before taking a reading.

Explain how the student could check the metre rule is horizontal before taking a reading.

The student places the block at the $80\text{cm}$ mark and pulls the force meter vertically downwards until the ruler is horizontal. The reading on the force meter is $1.45\text{N}$.

Calculate the mass $m$ of the block. You should take moments about the pivot.

The student wants to reduce the percentage uncertainty in the value obtained for the mass of the block.

The student moved the force meter towards the centre of gravity of the metre rule and repeated the measurements.

Deduce whether the percentage uncertainty in the value obtained for the mass of the block is reduced by the student moving the force meter. No calculations are required.

A sledge accelerates, due to gravity, from rest down a frictionless slope. Air resistance can be ignored. The slope is at an angle of 6.9° to the horizontal, as shown.

Complete the free‐body force diagram below for the sledge.

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The slope has a total length of 60m

i) Show that the initial acceleration of the sledge along the slope is about 1 m s⁻²

Initial acceleration = ........................................ (2)

ii) Determine the speed of the sledge at the end of the slope.

Speed at end of slope = .................................... (2)

iii) Determine the time taken for the sledge to travel to the end of the slope.

                        Time taken = ...................................... **(2)**

A toy car is released from rest and rolls down a slope, as shown.

mass of car = 0.160 kg

speed of car at bottom of slope = 2.6 m s^–1.

Calculate the increase in kinetic energy of the car as it accelerates down the slope.

Increase in kinetic energy = .......................................

As the car accelerates down the slope, the work done against frictional forces is 0.26 J.

Calculate the vertical displacement of the car.

Vertical displacement of car = ...................................

A light dependent resistor (LDR) and a fixed resistor are connected in a circuit, as shown.

The intensity of the light incident on the LDR is increased.

Which of the following does not take place as the light intensity is increased?

The diagram shows a cell of e.m.f. ε and internal resistance r. The cell is connected in series with two resistors of resistance R₁ and R₂. The potential difference across R₁ is V₁. The current in the circuit is I.

Which of the following expressions is correct?

Two waves leave the same source in phase. The waves travel along different paths and then meet. The wavelength of the waves is 8.0 cm.

Which of the following would cause constructive interference when the waves meet?

The diagram shows refraction of a ray of light as it passes through three transparent substances, L, M and N. The speeds of light in the three substances are v_L, v_M and v_N, respectively.

Which of the following shows the relationship between v_L, v_M and v_N?

The equation $I=nqvA$ relates the current in a sample of a material to the movement of free charge carriers in the sample.

Which of the following is a correct definition of one of the terms in this equation?

The diagram shows some of the energy levels of a hydrogen atom.

An excited electron in the level –0.54 eV drops to the level –13.60 eV, resulting in the release of at least one photon.

Which of the following photon energy values could not be produced from this electron transition?

Which of the following statements is correct for minimum displacement of the particles in a longitudinal wave?

A student determines the wavelength of the light emitted by a laser. She uses the laser, a diffraction grating and a screen.

Which of the following measurements is not required?

A student set up the circuit shown.

Calculate the number of electrons passing point X each second.

Number of electrons in one second = ..............................

Another resistor, Y, is added to the circuit as shown.

The student wrote the following statement.

Evaluate the student’s statement.

A cell of e.m.f. ε is connected in series with a variable resistor with resistance R as shown. The internal resistance of the cell is r.

When R is 12 Ω, the reading on the ammeter is 107 mA. The circuit is switched on for 300 seconds. In this time, 50 J of energy is transferred by the cell.

Calculate r.

r = .......................................................

Increasing R would make the terminal potential difference value closer to ε.

Explain why, without further calculation.

A voltmeter is added to the circuit as shown.

Explain how this circuit can be used to determine a value for r using a graphical method.

The interference of microwaves can be investigated in the laboratory using a microwave transmitter and receiver. A coherent beam of microwaves is directed at two slits, S₁ and S₂, formed between metal plates, as shown.

Describe what is meant by a coherent beam.

As the receiver is moved along line AB, alternate points of maximum and minimum readings are detected.

Explain why maximum and minimum readings are detected.

The receiver detects a maximum reading at point O, which is equidistant from the two slits.

The next two maximum readings are detected at P and Q.

Point Q is $85\text{cm}$ from S₁ and $75\text{cm}$ from S₂.

Three common microwave bands and their corresponding frequencies are given in the table.

Deduce the band of the microwaves used in this experiment.

When unpolarised light passes through a polarising filter, the light becomes plane polarised.

Explain the difference between unpolarised and plane polarized light.

An unpolarised light source is directed towards a screen. The intensity of radiation measured at the screen is 1.00 W m⁻².

Two polarising filters are placed between the light source and the screen.

Initially there is an angle of 0° between their planes of polarisation, as shown.

One of the polarising filters is then rotated, as shown.

Sketch a graph to show how the intensity of light measured at the screen varies as the filter is rotated from 0° to 90°.

Polarisation can be used to identify when some materials are under stress. Placing the material under stress causes the plane of polarisation of the light passing through the material to be rotated. The greater the stress, the greater the rotation of the plane of polarisation of the light.

A piece of transparent material under stress is positioned between two polarizing filters. There is an angle of 90o between the planes of polarisation of the two polarising filters.

Explain how this photograph can be used to identify areas of the material with different amounts of stress.