MJ22 P52 Q2 Cepheid Luminosity

9702/52/M/J/22: The brightness of some stars varies regularly. These stars are called variable stars. Fig. 2.1 shows the variation of luminosity with time for a variable star. A student determines the period T and mean luminosity L of the star. The student repeats the process for different variable stars.

It is suggested that L and T are related by the equation \(L = SKT^a\) where S is the luminosity of the Sun, and a and K are constants.

Sample solutions for practical Paper 5 variant 2 Question 2 May/June 2022 Cambridge A Level Physics.

MJ22 P52 Q1 Magnetic Launcher "Rail Gun" Metal Bar

9702/52/M/J/22: Two parallel cylindrical conductors each have a small cross‑sectional area A. A thin metal bar connects the two conductors, as shown in Fig. 1.1. The metal bar has a square cross‑section with sides of length y. For each conductor, the distance between its end C and the centre of the metal bar is L. The distance between the centres of the conductors is x.

The ends C are connected to a power supply and the current I in the conductors is measured.

It is suggested that I is related to L by the relationship

\(\dfrac{e}{I} = \dfrac{2PL}{A} + \dfrac{Qx}{y^2} \)

where E is the electromotive force (e.m.f.) of the power supply, and P and Q are constants.

Plan a laboratory experiment to test the relationship between I and L. Draw a diagram showing the arrangement of your equipment. Explain how the results could be used to determine values for P and Q.

Sample work sheet for planning before actually writing the solutions on the lines:

Sample solutions for practical Paper 5 variant 2 Question 1 May/June 2022 Cambridge A Level Physics.

FM22 P52 Q2 Oscilloscope Phase Angle

 9702/52/F/M/22: A student investigates a circuit containing a capacitor and a resistor as shown in Fig. 2.1. A dual‑beam oscilloscope is connected across the capacitor of capacitance C and resistor of resistance R. The oscilloscope displays two traces as shown in Fig. 2.2.

The student determines the phase difference θ between the two traces. The student repeats the experiment with different resistors. It is suggested that θ and R are related by the equation

\(\tan \theta = \dfrac{1}{2 \pi f C R}\)

where f is the frequency of the a.c. power supply.

Sample solutions for practical Paper 5 variant 2 Question 2 Feb/March 2022 Cambridge A Level Physics.

SP22 P5 Q1 Mutual Inductance of Two Coils

 9702/5/SP/22: A circular coil P carrying an alternating current produces a changing magnetic field. When a second similar coil Q is placed with its centre a distance x from the centre of coil P, as shown in Fig. 1.1, an electromotive force (e.m.f.) E is induced in coil Q.

It is suggested that E is related to x by the relationship \(E = IZe^{–kx}\) where I is the current in coil P, and k and Z are constants.

Plan a laboratory experiment to test the relationship between E and x.

Draw a diagram showing the arrangement of your equipment.

Explain how the results could be used to determine values for k and Z.

Sample solutions for practical Paper 5 Question 1 Specimen Paper 2022 Cambridge A Level Physics.

ON21 P52 Q2 GM Tube Radiation

9702/52/O/N/21: A Geiger–Müller (G–M) tube is a device that can detect beta-radiation. A student places paper between a radioactive source emitting beta-radiation and a G–M tube, as shown in Fig. 2.1. The G–M tube is connected to a rate-meter which records the count rate R. The thickness t of the paper is measured in two different places using a micrometer. The student repeats the experiment for different thicknesses of paper.

It is suggested that R and t are related by the equation \(R =R_0 e^{-\mu t} \) where \(R0\) is the count rate without any paper and μ is a constant.

Sample solutions for practical Paper 5 variant 2 Question 2 October/November 2021 Cambridge A Level Physics.

MJ21 P51 Q2 Glider Collision

 9702/51/M/J/21: A student investigates the collision of two gliders A and B on a linear air-track. A card is attached to glider B, as shown in Fig. 2.1. Glider B has a mass M. A mass m is added to glider B. Glider A travels at a constant velocity u towards the stationary glider B. The gliders then collide and move together towards the light gate. The card passes through the light gate which is connected to a data logger. The student records the velocity v of the two gliders from the data logger.

The student changes the mass m and repeats the experiment. It is suggested that v and m are related by the equation \(Au = (M + m + A)v\) where A is the mass of glider A.

Sample solutions for practical Paper 5 variant 1 Question 2 May/June 2021 Cambridge A Level Physics.

FM21 P52 Q2 Glider Collision Speed

 9702/52/F/M/21: A student investigates the collision of two gliders A and B on a linear air-track, as shown in Fig. 2.1. The light gate is connected to a timer. A card of length L is attached to glider B. The mass of glider B and the card is m. Glider B is initially at rest.

The student releases glider A so that it travels at a constant velocity u towards the stationary glider B. The gliders collide and then separate. The card on glider B passes through the light gate. The student records the time t for the card to pass through the light gate from the timer.

The student changes the mass of glider B and repeats the experiment.

It is suggested that the velocity v of glider B as it passes through the light gate and m are related by the equation

\(v = \dfrac{2uA}{m + A} \)

where A is the mass of glider A.

Solutions for practical Paper 5 variant 1 Question 2 February/March 2021 Cambridge A Level Physics.

FM21 P52 Q1 Oscillating Cylinder in Liquid

 9702/52/F/M/21: A student investigates the vertical oscillations of a solid cylinder which floats in cooking oil. Fig. 1.1 shows a cylinder of radius r. The student places the cylinder of mass m in the oil. The cylinder is displaced vertically from its equilibrium position and released so that it oscillates. The period T of the oscillations is determined. A number of cylinders of different mass are available.

It is suggested that the relationship between T and m is 

\(T = 2 \sqrt{\dfrac{\pi m}{\sigma K r^2}} \)

where σ is the density of the oil and K is a constant. 

Design a laboratory experiment to test the relationship between T and m. Explain how your results could be used to determine a value for K.

Solutions for practical Paper 5 variant 1 Question 1 February/March 2021 Cambridge A Level Physics.

Paper 5 Q1 Answer Template (A Level 9702 Physics)

What is this practical paper about? Here's an intro briefing!

 

Important: Break your answer into sections with headers, and use point form when writing your answer! 

 

A) DIAGRAM

• Use ruler, draw a clear diagram (show relative positions of apparatus) 
• Label all apparatus (including the table!) 

 

B) DEFINING THE PROBLEM

• Independent variable: __________________ 
• Dependent variable: ___________________ 
• Constant variables: ___________________ (list 2-3 other possible variables) 

 

C) METHODS OF DATA COLLECTION

1.    Set up the apparatus as shown in the diagram above.
2.    Vary the independent variable by _______________	❑ Include details how to vary ❑ Take preliminary readings to ensure workable range of variables ❑ Any safety considerations?
3.    Measure the constant variable by ____.	❑ Include details how you would know the constant variable is unchanging. ❑ Measuring instrument(s) used
4.    Measure the independent variable by ______________. *Clearly describe procedure in a logical sequence	❑ Include details on method & technique for reliable results ❑ Measuring instrument(s) used ❑ Any safety considerations? ❑ Any limitations/suggestions?
5.    Measure the dependent variable by ______________. *Clearly describe procedure in a logical sequence	❑ Include details on method & technique for reliable results ❑ Measuring instrument(s) used ❑ Any safety considerations? Any limitations/suggestions?
6.    Repeat procedure to obtain an average value for ________ (dependent variable)	❑  Details of averaging method to reduce uncertainty from random errors
7.    Repeat steps ________ to _________ for different values of ______________ (independent variable)	❑  Mention how constant variables made sure they are kept constant as steps are repeated

 

D) METHOD OF ANALYSIS

1.    In the given equation, p is _______, q is ________, and _______________ are constants.	❑  Identify IV/DV symbols ❑ Identify constants
2.    Include math steps to linearize equation. e.g. Taking log on both sides, log(y) = n log(x) + log(k)	❑  Put equation in linear form Y = mX + C
3.    Plot a graph of _______ against _______
4.    If the above relationship is true, a straight line graph will be obtained where the gradient is equal to _______ and the y-intercept is equal to ______________.   (constant to find) = ___(expression)_____.	Include expressions for ❑  Gradient ❑  y-intercept ❑ Constant to find

E) ANY ADDITIONAL DETAILS

*if it's not already included in Section C Methods

❑ List at least 2 safety considerations 

❑ List at least 3 suggestions to improve accuracy/reliability of results 

❑ Any other steps you missed in Section C. 

 

 

 Paper 5 Q1 Tutorial with sample MJ16 P52 Q1:

 

More Paper 5 videos in the playlist:
https://www.youtube.com/playlist?list=PLXli3LrRvG-YW3-uua5FyY3Tb2l1WT6UD

 

 Image version of template to use:

ON20 P35 Q2 Sample Lab Practical

 9702/35/O/N/20:

Lab report sample for October/November 2020 Paper 3 Variant 5 Question 2.

ON20 P35 Q1 Sample Lab Practical

9702/35/O/N/20:

Sample lab report for October/November 2020 Paper 4 Variant 5 Question 1. 
Also known as 9702w20qp35

ON20 P11 Worked Solutions

9702/1/O/N/20: Full video playlist here:

https://youtube.com/playlist?list=PLXli3LrRvG-avEwF0UuNQSZE-VPKM05Iu

  Also known as 9702w20qp11

MJ20 P52 Q2 Viscosity of Liquid

 9702/52/M/J/20: A student investigates how the viscous force in a liquid varies with temperature.
The student releases a ball from the surface of the liquid in a container. The ball falls as shown in
Fig. 2.1. The student determines the speed of the ball between P and Q and measures the thermodynamic
temperature T of the liquid.

Viscosity is a term used to describe the viscous forces acting in a liquid. Viscosity has the unit
pascal second (Pas). The viscosity η of the liquid is calculated from the speed of the ball. The experiment is repeated for the same liquid at different temperatures. It is suggested that η and T are related by the equation 

\( \eta = He^{\frac{E}{kT}}\)

where E and H are constants and k is the Boltzmann constant.

May/June 2020 Paper 5 Variant 2 Questions 2 data analysis.

 

MJ20 P51 Q2 Discharging Capacitor

9702/51/M/J/20: A student investigates the discharge of a capacitor through a resistor using the circuit shown in Fig. 2.1. The student initially closes the switch and charges the capacitor. The switch is then opened and a stop-watch is started. The capacitor discharges through the resistor. At time t the potential
difference V across the capacitor is measured.

It is suggested that V and t are related by the equation where Q0 is the charge of the fully charged capacitor, C is the capacitance of the capacitor and R is the resistance of the resistor.

 May/June 2020 Paper 51 Question 2.

 

MJ20 P12 Worked Solutions

9702/12/M/J/20: Full video playlist here:

https://www.youtube.com/playlist?list=PLXli3LrRvG-ZqeckKG8SuUzNszFbpQXD0

  Also known as 9702s20qp12