What kind of thermal energy that flows between objects due to a difference in temperature?

Give an example in which the electrical energy changes to light energy

Aheat engine that operates on a carnot cycle has an efficiency of 0.420 when its low-temperature reservoir is at 10 ∘c.part aby how many degrees celsius must you increase the temperature of the high-temperature reservoir to increase the efficiency to 0.600 if you continue to use the same low-temperature reservoir?

The voltmeter reads 117 v and ammeter reads 0.13 a .if the resistance of ammeter and voltmeter are 9 kilo ohm and 0.015 ohm respectively ,find the value of r. 3marks