Advertisements
Advertisements
प्रश्न
A current passes through a resistor. Let K1 and K2 represent the average kinetic energy of the conduction electrons and the metal ions, respectively.
पर्याय
K2 < K2
K1 = K2
K1 > K2
Any of these three may occur
Advertisements
उत्तर
K1 > K2
The metal ions are bound at their positions and vibrate due to collisions with electrons and due to thermal energy. The conduction electrons are free to move. They get energy from the electric field set inside the conductor by connection with a battery and due to thermal motion. The velocity of the electrons is high.
Thus, the kinetic energy of the electrons is greater than the kinetic energy of the metal ions.
APPEARS IN
संबंधित प्रश्न
When a current of 4.0 A passes through a certain resistor for 10 minutes, 2.88 × 104 J of heat are produced. Calculate
the power of the resistor.
the voltage across the resistor.
Write an expression for the electrical power spent in flow of current through a conductor in terms of
(a) Resistance and potential difference, (b) current and resistance.
Electrical power P is given by the expression P = (Q × V) ÷ time. What do the symbols Q and V represent?
1Kwh =`( 1 "volt "xx 1 am pere xx.............)/1000`
When a current I flows through a resistance R for time t, the electrical energy spent is given by:
(a) IRt (b) I²Rt (c) `IR^2t` (d) `I^2R ⁄t`
A bulb of 40 W is used for 12.5 h each day for 30 days. Calculate the electrical energy consumed.
An electric bulb marked 220 V, 100 W will get fused if it is made to consume 150 W or more. What voltage fluctuation will the bulb withstand?

The diagram above shows a circuit with the key k open. Calculate :
(i) the resistance of the circuit when the key k is open.
(ii) the current drawn from the cell when the key k is open.
(iii) the resistance of the circuit when the key k is closed.
(iv) the current drawn from the cell when the key k is closed.
A simple electric circuit has a 30 V battery and a resistor ot 60 o. What will be the current in the circuit? The resistance of the oonnecting wires is negligible.
An electric bulb of resistance 500 Ω draws current 0.4 A from the source. Calculate:
- the power of bulb and
- the potential difference at its end.
Express watt hour and kilowatt hour in joule.
State the position of heating element with respect to principal focus of concave reflector and give reason for choosing this position.
Which material is the calorimeter commonly made of? Give one reason for using this material.
Three 250 W heaters are connected in parallel to a 100 V supply, Calculate the resistance of each heater.
A bulb is connected to a battery of e.m.f. 6V and internal resistance 2Ω A steady current of 0.5A flows through the bulb. Calculate the total energy supplied by the battery in 10 minutes.
An immersion rod having resistance of 50 Ω is connected to 220V main supply. Assuming that all the energy generated goes to heat the water, calculate the time taken to heat 5 kg water from 30°C to 100°C.
1 mV is equal to:
Electric power is inversely proportional to ____________.
