Thermal Properties of Matter Quiz 4

One end of copper rod is in contact with water at 100 °C and the other end in contact with ice at 0 °C. The length of the rod is 100 cm. At a point which is at a distance of 35 cm from the cold end, temperature is (assuming steady state heat flow)

In Newton’s law of cooling, the rate of fall of temperature

The metal sphere cools at 1 °C/min, when its temperature is 50 °C. If the temperature of environment is 30 °C, its rate of cooling at 35 °C is

A copper rod of 88 cm and an aluminium rod of unknown length have their increase in length independent of increase in temperature. The length of aluminum rod is: ($(a_{Cu} = 1.7 \times 10^{-5}K^{-1} \text{ and } \alpha _{Al} = 2.2 \times 10^{-5} K^{-1} )$

The unit of thermal conductivity is:

An object kept in a large room having air temperature of 25°C takes 12 minutes to cool from 80°C to 70°C. The time taken to cool for the same object from 70°C to 60°C would be nearly.

A copper ball of mass 100 g is at a temperature T. It is dropped in a copper calorimeter of mass 100 g, filled with 170 g of water at room temperature. Subsequently, thetemperature of the system is found to be 75 °C. T is given by: (Given: room temperature = 30°C, specific heat of copper 0.1 cal/g °C)

A piece of ice falls from a height h so that it melts completely. Only one quarter of the heat produced is absorbed by the ice and all energy of ice gets converted into heat during its fall. The value of h is [Latent heat of ice is $3.4 \times 10^5 J/kg$ and g = 10 N/ kg]

For which of the following process, the thermal conduction is maximum?

The good absorber of heat are