2. a) A student obtained ice at 0°C from a refrigerator and placed it in a beaker on a bench. After 4 minutes, the temperature rose to 4°C. State the changes that would be observed in the water in terms of;
(i) volume
(ii) mass
(iii) density

(b) Sketch a graph of density against temperature if the ice is warmed from 0°C to
8°C.

The image shows a pendulum in simple harmonic motion the pendulum starts at a and swing to e

Explain earth's motion, using the terms "precession" and "rotation" in your answer.

Air enters a gas turbine with two stages of compression and two stages of expansion at 100 kpa and 17°c. this system uses a regenerator as well as reheating and intercooling – the intercooler returns the air to the inlet temperature. the pressure ratio across each compressor is 4 ; 300 kj/kg of heat are added to the air in each combustion chamber; and the regenerator operates perfectly while increasing the temperature of the cold air by 20°c. determine the system’s thermal efficiency. assume isentropic operations for all compressor and the turbine stages and use constant specific heats at room temperature. (0.378)