A student measures the resistance of 0.20 m, 0.40 m and 0.60 m of one uniform wire. Values are 1.6 Ω, 3.2 Ω and 5.6 Ω. The 0.60 m measurement is made after current has flowed for several minutes.
.1
Use the first two results to calculate the expected resistance of 0.60 m of wire at the original temperature.
[2 marks]
.2
Evaluate the final result and suggest how to improve the investigation.
[3 marks]
5 marksFoundation and Higher
Spec and skills
Original practice question
Answer and supported method checks
In a specific heat capacity investigation, a 0.60 kg block receives 7200 J from a heater. Its temperature rises from 18 °C to 38 °C. A second run with the same block and input energy gives a rise of only 16 °C.
.1
Calculate the specific heat capacity using the first run.
[3 marks]
.2
The student claims that the second run proves the metal has changed. Evaluate the claim and describe one check on the temperature measurement.
[2 marks]
4 marksHigher
Spec and skills
Original practice question
Answer and supported method checks
A heater supplies 12000 J to 0.10 kg of ice already at 0 °C. The specific latent heat of fusion is 334000 J/kg. Assume no energy reaches the surroundings.
.1
Calculate the mass of ice that melts.
[2 marks]
.2
Evaluate the statement that the final temperature must be above 0 °C because energy was supplied.
[2 marks]
6 marksFoundation and Higher
Spec and skills
Original practice question
Answer and supported method checks
A worker is near a sealed radioactive source for a short time. Another worker has radioactive dust on a glove. A supervisor recommends tongs, shielding and careful removal of the contaminated glove.
Explain the different hazards and how the precautions reduce them.
[6 marks]
6 marksHigher
Spec and skills
Original practice question
Answer and supported method checks
A region can add a nuclear plant or a gas-fired plant. It needs steady electricity for many years and aims to reduce carbon dioxide emissions. The nuclear plant costs more to build and produces radioactive waste.
Evaluate the two choices against the region's aims. Give a supported recommendation.
