Complete the following by choosing the correct answers from the bracket: (a) In uniform circular motion the centrifugal force acts ............... [towards the centre/away from the centre/along the tangential direction]. (b) Refractive index of a medium is independent of ............... [temperature/angle of incidence/wavelength of light]. (c) Heat absorbed during change of phase depends on ............... [mass/change in temperature/specific heat capacity] of the substance. (d) Emf of a cell is ............... [greater than/less than/equal to] the terminal voltage when the cell is in open circuit. (e) In a step-up transformer the turns ratio is ............... [more than 1/less than 1/equal to 1]. (f) The nuclear radiation with lowest ionising power is ............... [α/β/γ].

Each of the substances given below is supplied with same amount of heat. Which one will attain the highest temperature? Substance Specific heat capacity (cal/g°C) Lead 0.031 Aluminium 0.21 Copper 0.095 Iron 0.115 (a) Aluminium (b) Copper (c) Iron (d) Lead

A metal piece of mass 5 g has thermal capacity 2.5 J K⁻¹. If the mass of the metal is tripled, then its specific heat capacity will be : (a) 7.5 J K⁻¹ (b) 2.5 J K⁻¹ (c) 1.5 J g⁻¹ K⁻¹ (d) 0.5 J g⁻¹ K⁻¹

(a) A certain amount of heat will warm 1 g of material X by 10°C and 1 g of material Y by 40°C. Which material has higher specific heat capacity? (b) Which material, X or Y, would you select to make a calorimeter? (c) The specific heat capacity of a substance remains the same when it changes its state from solid to liquid. State True or False.

30 g of ice at 0°C is used to bring down the temperature of a certain mass of water at 70°C to 20°C. Find the mass of water. Specific heat capacity of water = 4.2 J g⁻¹ °C⁻¹ and specific latent heat of ice = 336 J g⁻¹.

Thermal capacities of substances A and B are same. If mass of A is more than mass of B then: (a) Which substance will have more specific heat capacity? (b) Which substance will show greater rise in temperature if the same amount of heat is supplied to both?

fHow much heat is required to convert 500 g of ice at 0°C to water at 0°C? The latent heat of fusion of ice is 330 J g−1.

A metal piece of thermal capacity 40 J K−1 absorbs 800 J of heat. Calculate the rise in the temperature of this metal piece.

Calculate the total amount of heat energy required to melt 200 g of ice at 0°C to water at 100°C. (Specific latent heat of ice = 336 J g−1, specific heat capacity of water = 4.2 J g−1 °C−1)

Specific heat capacity of a substance X is 1900 J kg−1 °C−1 means: (a) Substance X absorbs 1900 J for 1°C rise in temperature (b) 1 kg of substance X absorbs 1900 J heat for 1°C rise in temperature (c) 1 kg of substance X absorbs 1900 J heat to increase the temperature (d) 1 kg of substance X absorbs 1900 J heat to cool down by 1°C

(a) State the principle of calorimetry. (b) Name the material used for making a calorimeter. (c) Write one characteristic property of the material chosen for making a calorimeter.

Specific latent heat of a substance: (a) is directly proportional to the mass (b) is directly proportional to the change in the temperature (c) depends on the material (d) is inversely proportional to the mass