Advertisements
Advertisements
Question
If the current passing through a conductor is doubled, what will be the change in heat produced
Advertisements
Solution
If the current passing through a conductor is doubled, the heat produced will increase by four times because the heat produced is directly proportional to the square of the current
APPEARS IN
RELATED QUESTIONS
Three 2 V cells are connected in series and used as a battery in a circuit.
What is the p.d. at the terminals of the battery?
Which particles constitute the electric current in a metallic conductor?
One coulomb of charge flows through any cross-section of a conductor in 1 second. What is the current flowing through the conductor?
An electric bulb of resistance 20 Ω and a resistance wire of 4 Ω are connected in series with a 6 V battery.
Draw the circuit diagram, and calculate:
(a) total resistance of the circuit.
(b) current through the circuit.
(c) potential difference across the electric bulb.
(d) potential difference across the resistance wire.
Ten bulbs are connected in a series circuit to a power supply line. Ten identical bulbs are connected in a parallel circuit to an identical power supply line.
(b) In which circuit, if one bulbs be brighter?
Consider the circuit given below when A, B and C are three identical light bulbs of constant resistance.
(a) List the bulbs in order of increasing brightness.
(b) If C burns out, what will be the brightness of A now compared with before?
(c) If B burns out instead, what will be the brightness of A and C compared with before?
A given wire of resistance 1 Ω is stretched to double its length. What will be its new resistance?
A battery of e.m.f. 15 V and internal resistance 3 ohm is connected to two resistors of resistance 3 ohm and 6 ohm in series. Find:
(i) The current through the battery,
(ii) The p.d. between the terminals of the battery.
Explain with the help of a diagram how does 'short circuiting' occur in an electric kettle.
Tick (✓) the correct choice among the following :
In fig .XY is at right angles to the magnetic field. The direction in
which XY should be moved to induce an electron flow in the direction Y to X as indicated by the arrow is
Electrical power P is given by the expression P = (Q × V) ÷ time
(a) What do the symbols Q and V represent?
(b) Express the power P in terms of current and resistance explaining the meanings of symbols used there in.
State the S.I. units of electrical power.
What is the speed of electric current?
The power of an electric device is a product of ______ and ______.
- What is meant by electric current?
- Name and define its unit.
- Which instrument is used to measure the electric current? How should it be connected in a circuit?
For current to flow, one needs art open circuit.
