State the functions of the following in a nuclear reactor:-
i) Moderator ii) Control rods iii) Coolanti) Mention two important precautions that should be taken while handling radioactive materials.
ii) State any one use of radioisotopes.
The combination of a movable pulley P1 with a fixed pulley P2 is used for lifting up a load W.
i) State the function of the fixed pulley P2.
ii) If the free end of the string moves through a distance C, find the distance by which the load W is raised.
iii) Calculate the force to be applied at C to just raise the load W = 20 kgf, neglecting the weight of the pulley P1and friction.
A solid body weighs 2.10 N in air. Its relative density is 8.4. How much will the body weigh if placed:-
i) in water,
ii) in a liquid of relative density 1.2?i) What is meant by refraction?
ii) Express the refractive index n of a medium,
i) Refraction is the phenomenon in which a ray of light bends from its path as it attempts to move from one medium into another.
ii) 1. n =
2. n =
iii) It means that the refractive index of both the medium is the same.
If there is no heat loss to the surroundings, the heat released by the condensation of m2 g of ice at 0oC into water at 0o C.
i) Find:
1. The heat lost by the steam in terms of m1.
2. the heat gained by ice in terms of m2.
ii) Form a heat equation and find the ratio of m2: m1 from it.
In the figure given alongside, A, B and C are three ammeters. The ammeter B reads 0.5 A. All the ammeters have negligible resistance.
Calculate:
i) The readings in the ammeter A and C.
ii) The total resistance of the circuit.i) Draw a labeled diagram of a hot cathode ray tube.
ii) Why are materials of low work function preferred as thermionic cathode materials?
iii) Write an equation to show the fission of a nucleus of U235 with the production of three neutrons.