Physics
The melting point of naphthalene is 80°C and the room temperature is 30°C. A sample of liquid naphthalene at 100°C is cooled down to the room temperature. Draw a temperature time graph to represent this cooling. In the graph, mark the region which corresponds to the freezing process.
Related Questions
(i) Define Calorimetry.
(ii) Name the material used for making a Calorimeter.
(iii) Why is a Calorimeter made-up of thin sheets of the above material answered in (ii) ?
104 g of water at 30°C is taken in a calorimeter made of copper of mass 42 g. When a certain mass of ice at 0°C is added to it, the final steady temperature of the mixture after the ice has melted, was found to be 10°C. Find the mass of ice added.
[Specific heat capacity of water = 4.2 J g-1 °C-1; Specific latent heat of fusion of ice = 336 J g-1; Specific heat capacity of copper = 0.4 J g-1 °C-1 ]Draw a neat labelled diagram of an AC generator.
The diagram shows a circuit with the key k open. Calculate:
(i) the resistance of the circuit when the key k is open.
(ii) the current drawn from the cell when the key k is open.
(iii) the resistance of the circuit when the key k is closed.
(iv) the current drawn from the cell when the key k is closed.