Advertisements
Advertisements
प्रश्न
Find the heat produced in joules when a current of 10 amperes flows through a connecting wire of resistance 2 × 10-2 ohms and heating element of resistance 250 ohms for 2 seconds.
Advertisements
उत्तर
Heat produced when current flows in the wire for 2 seconds
Q1 = I2Rt
Q1 = 10 × 10 × 2 × 10-2 × 2
Q1 = 4 J
Heat produced in heating element in 2 seconds
Q2 = 10 × 10 × 250 × 2
Q2 = 50000 J
संबंधित प्रश्न
An electric bulb is rated at 220 V, 100 W. (a) what is its resistance? (b) what safe current can be passed through it?
A current passes through a resistor. Let K1 and K2 represent the average kinetic energy of the conduction electrons and the metal ions, respectively.
What is the current in the circuit shown (Fig. )

The diagram 31 shows a 3 terminal plug socket.
(i) What is the purpose of the terminal E?
(ii) To which part of the appliance is the terminal E connected?
(iii) To which wire L or N, is the fuse connected and why?

Why is heating element wound on a long porcelain rod in a room heater.
Why is the heating element of an electric oven wound on a helix? State the reason.
I ampere of current is passed through a resistor of resistance R ohm for time t second. Obtain expression for
(i) the electrical energy, and
(ii) the electrical power spent.
How can electric energy consumed by an electric appliance be calculated in kilowatt hour (kWh)?
A battery of e.m.f. 12V and internal resistance 1.6 Ω is connected to two resistors of 4Ω and 6Ω connected in parallel. Calculate:
(i) the current drawn from the battery,
(ii) the power dissipated in each resistor,
(ii)the total power supplied by the battery.
A student wants to use an electric heater, an electric bulb and an electric fan simultaneously.
How should these gadgets be connected with the mains? Justify your answer giving three reasons.
