(i) 85 g of water at 30°C is cooled to 5°C by adding mass of ice.Find the mass of ice required. [Specific heat capacity of water = 4.2 Jg^-1°C^-1,Specific latent heat of fusion=336 Jg^-1 (ii) (a) Why does it become pleasantly warm when the lakes start freezing?
(b) Water freezes to form ice. What change would you expect in the average energy of the molecules? (c) Which will contain more heat energy 1 g of ice at 0°C or 1 g water at 0°C?

(iii) (a) State one factor that affects the magnitude of induced current in an AC generator (b) Water freezes to form ice.What change would you expect in the average kinetic energy of the molecules? (c) Which will contain more heat energy 1g of ice at 0°C or 1g water at 0°C?

(iii) (a) State one factor that affects the magnitude of induced current in an AC generator
(b) Given below is a circuit to study the magnetic effect of electric current. ABCD is a cardboard kept perpendicular to the conductor XY. A magnetic compass is placed at the point P of the cardboard P1 and P2 are the positions of the magnetic compass, before and after passing a current through XY respectively.



1. Name the rule that is used to predict the direction of deflection of the magnetic compass.
2. State the direction of current in the conductor (X to Y or Y to X) when the circuit is complete.
3. If resistance R is increased,then what will be the effect on the magnetic

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