A parachutist has reached a first terminal velocity before opening a parachute. Consider the motion from just before opening until a new terminal velocity is reached.
Explain the changes in resultant force, acceleration and speed throughout this sequence.
[6 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]
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]
5 marksFoundation and Higher
Spec and skills
Original practice question
Answer and supported method checks
A student builds a circuit with a 9.0 V supply, a 10 Ω resistor and a 20 Ω resistor in series. The ammeter reads 0.30 A. The student writes: “The 20 Ω resistor uses twice as much current as the 10 Ω resistor.”
.1
Calculate the potential difference across the 10 Ω resistor.
[2 marks]
.2
Evaluate the statement using current conservation and energy transfer.
[3 marks]
5 marksFoundation and Higher
Spec and skills
Original practice question
Answer and supported method checks
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.
