5 marksFoundation and Higher6.2.2 Series and parallel circuits6.2.1.3 Current, resistance and potential difference
The diagram shows two resistors connected in parallel to a 12 V battery.
.1Calculate the current through the 6 Ω resistor.
[2 marks] .2The current through the 12 Ω resistor is 1 A.
Calculate the current supplied by the battery.
[1 mark] .3Explain why the total resistance of the circuit is less than 6 Ω.
[2 marks] 5 marksFoundation and Higher6.3.2.3 Changes of state and specific latent heat6.3.2.1 Internal energy
A block of ice is heated at a steady rate. The graph shows how its temperature changes.
0481216202428324080120Time (min)Temperature (°C)ABCD
.1In which section of the graph is the water boiling?
[1 mark] .2Explain why the temperature does not change in section B, even though energy is still being transferred to the ice.
[2 marks] .3The mass of the ice is 0.50 kg. The specific latent heat of fusion of ice is 334 000 J/kg.
Calculate the energy needed to melt all of the ice.
[2 marks] 6 marksFoundation and HigherRequired practical 156.2.1.3 Current, resistance and potential difference
A student measures the resistance of a length of wire. The diagram shows the correct circuit.
.1How is the voltmeter connected to the wire R?
[1 mark] .2The voltmeter reads 3.0 V. The ammeter reads 150 mA.
Calculate the resistance of the wire.
[3 marks] .3The student switches the circuit off between readings. Suggest why.
[2 marks] 4 marksFoundation and Higher6.4.2.2 Nuclear equations6.4.2.1 Radioactive decay and nuclear radiation
Radium-226 decays by emitting an alpha particle:
88226Ra→ZARn+24He.1Determine the mass number A of the radon nucleus.
[1 mark] .2Determine the atomic number Z of the radon nucleus.
[1 mark] .3Strontium-90 decays by beta emission. Describe what happens in the nucleus during beta decay.
[2 marks] 6 marksFoundation and Higher6.1.1.4 Power6.1.1.2 Changes in energy
An electric motor in a lift raises the lift through a height of 12 m in 20 s. The mass of the lift is 800 kg.
Gravitational field strength = 9.8 N/kg.
.1Calculate the energy transferred to the lift's gravitational potential store.
[2 marks] .2Calculate the useful power output of the motor.
[2 marks] .3A second motor raises the same lift through the same height in 30 s.
Explain why the second motor has a lower power output.
[2 marks] 