7 questions · 70 marks · ≈ 70 min
The Hertzsprung–Russell diagram shows stars classified into different regions. A B Absolute magnitude C D Colour
The boxes give four points, A, B, C and D, and four star classifications. Draw lines connecting each point to the correct star classification. Point Star classification A star similar to the Sun B white dwarf C red giant D very bright blue star
Describe what is meant by the term absolute magnitude.
Describe an investigation to determine the speed of sound. You may draw a diagram to help your answer.
A microphone is connected to an oscilloscope. A sound is detected by the microphone. The diagram shows the oscilloscope trace. Oscilloscope settings y direction: 1 square = 0.1 V x direction: 1 square = 5.0 ms
Determine the period of the sound wave. period = s
Calculate the frequency of the sound wave. frequency = Hz
The SPS is a particle accelerator in Geneva. The SPS can accelerate sulfur particles to speeds almost as fast as the speed of light.
Neutral sulfur particles can become positively charged sulfur particles. Describe the difference between a neutral sulfur particle and a positively charged sulfur particle.
Diagram 1 shows a section of the SPS. positive negative plate plate P Diagram 1 Positively charged sulfur particles are introduced at point P and accelerate to the right. Explain why the positively charged sulfur particles accelerate.
The sulfur particles enter a large tube and complete a circular orbit. Diagram 2 shows a sulfur particle, travelling with velocity v, in the tube. v F Diagram 2
A magnetic force acts on the positively charged sulfur particle. This force makes the particle travel in a circle. The force is labelled F. Use the left-hand rule to determine the direction of the applied magnetic field. A opposite to the direction of the velocity B along direction of force C out of the page D into the page
The tube has a radius of 1.1 km and the sulfur particle has an orbital speed of 2.9 × 10⁸ m/s. Calculate the orbital period of the sulfur particle. orbital period = s
A student heats a sample of water. The student measures the temperature of the sample of water during heating.
The sample of water has a mass of 0.45 kg. Calculate the energy required to increase the temperature of the water from 16 °C to 100 °C. [specific heat capacity of water = 4200 J / kg °C] energy = J
The diagram shows the temperature-time graph for the sample of water. 200 160 120 Temperature in °C 0 2 4 6 8 10 Time in minutes
Use the graph to determine the time taken from when the water started to boil to when the water stopped boiling. time taken = minutes
The heater used to heat the water has a power rating of 2200 W. Calculate the energy required to boil all of the water. energy = J
Give a reason why the liquid water should be stirred during the heating.
When water boils, the liquid water becomes a gas called steam. Describe the changes in arrangement and motion of the molecules in liquid water and the molecules in steam.
The diagram shows part of the National Grid. pylon power station step-up transformer
There is a step-up transformer at the power station end of a transmission line and a step-down transformer at a distant town. Explain why step-up transformers and step-down transformers are used in this way.
State the formula linking the input voltage, the output voltage and the turns ratio for a transformer.
The primary coil on a step-up transformer has 3300 turns. Calculate the number of turns required on the transformer’s secondary coil to step up the voltage from 15 kV to 340 kV. number of turns =
Transformers in the National Grid have efficiencies less than 100%.
Suggest which energy store of the transformer increases as a result of the efficiency being less than 100%.
The iron core of a transformer is an electrical conductor. When the transformer is in use, the primary coil causes a changing magnetic field in the iron core. This causes a small current to be induced in the core. Explain how a current is induced in the core of the transformer.
The refractive index, n, of a material can be calculated using this formula. sin(i ) n= sin(r )
A student uses this method to determine the refractive index of a material.
Name the independent variable in this investigation.
The table shows the student’s results for an angle of incidence of 40°. Angle of refraction 1 (°) Angle of refraction 2 (°) Angle of refraction 3 (°) 22 23 67 Calculate the mean value for the angle of refraction. mean angle = degrees
Describe how the student could improve their method to get a more accurate value for the refractive index.
Diagram 1 shows a ray of light refracted by a transparent block of material. 82° air material 47° Diagram 1
Calculate the refractive index of this material. refractive index =
State the formula linking critical angle and refractive index.
The refractive index of a different material is 1.7 Calculate the critical angle of this material. critical angle = degrees
Diagram 2 shows a ray of light travelling through an optical fibre. Diagram 2 The optical fibre is made of a material with a refractive index of 1.7 Explain the path of the ray in the optical fibre.
Diagram 1 shows a gate fitted with a spring mechanism. The spring mechanism shuts the gate automatically. gate spring mechanism Diagram 1
The graph shows some data from an investigation into how the extension of the spring changes with an increasing force. Extension in cm 0 100 200 300 400 500 Force in N Describe the relationship shown by the graph.
Diagram 2 shows the gate viewed from above. F 320 cm pivot 84 cm spring gate mechanism 480 N Diagram 2 The force the spring exerts on the gate is 480 N. Show that the moment of the force the spring exerts on the gate is about 400 Nm.
The force, F, is the minimum force needed to start opening the gate. Calculate the magnitude of force F. force F = N
The spring is removed for testing. Explain what will happen to the spring if the force applied to extend the spring is too large.