An electric iron rated 1100 W, 220 V is operated for 5 hours. Calculate: (a) the minimum rating of the fuse required. (b) the energy consumed in kWh. (c) the cost of the energy consumed, if the rate is ₹10 per unit.

The diagram shows wiring in a meter room of a building. (a) What is the current rating of device X? (b) What is the difference between switch Z shown in the diagram and the switches used to operate different appliances at home? (c) What is the unit of the physical quantity displayed in Y?

According to the NEW colour convention which colour of wire is connected to: (a) the metal body of the appliance (b) the switch of the appliance?

(a) Which electrical component protects the electric circuit in case of excess current and which can also be used as a switch? (b) Name the wire to which this electrical component is connected in an electric circuit.

A fuse is rated 5 A. Can it be used with a geyser rated 1540 W, 220 V. Write Yes or No. Give supporting calculations to justify your answer.

Identify the option that displays the correct wiring with correct colour code: (a) (b) (c) (d)

Bulb A rated 160 W, 40 V and Bulb B rated 40 W, 40 V are connected as shown in the diagram. (a) Calculate the ratio V1 : V2. (b) If bulb A fuses, the current in the circuit remains the same. State True or False.

To lift a load of 30 kgf, Suhas uses a single fixed pulley while Radha uses a single movable pulley. The displacement of efforts in both cases is equal. In an ideal situation calculate the ratio of: (a) the efforts in the two cases. (b) the potential energy gained by the loads in the two cases. (c) the efficiencies in the two cases.

(a) Name the unit of work done used on the subatomic scale. (b) To which class of lever does a pair of scissors belong? (c) A stone is tied to a string and displaced from A to B by application of constant force F in three different ways as shown below. Arrange the three cases in ascending order of the work done by the force. (Given AJB is a semicircle, θ < 90° and AB = 20 m)

(a) Atmospheric temperature after a hailstorm is greater than the temperature during the hailstorm. State True or False. (b) Which thermal physical quantity of a frying pan changes by making its base heavier? (c) State the principle of Calorimetry.

A type of glass block has a refractive index of 1.8. (a) Calculate the speed of light in this glass. (Given speed of light in air = 3 × 108 m s−1) (b) If the width of this block is doubled, then what will be the speed of light in the block?

A ray of light enters a glass block from air and comes out from the opposite surface. If the angle of refraction at the first surface is not the same as the angle of incidence at the second surface, then: (a) What is the product of the ratio sin i / sin r at the first surface and at the second surface? (b) State whether the opposite surfaces are parallel or not parallel. (c) How did you reach the conclusion in (b) above?