Science Answer the questions.[Phy-1M]

State the SI unit of resistivity.

State the relation between potential difference, work done and charge moved.

State the factors on which the strength of electric current flowing in a given conductor depends.

One coulomb of charge flows through any cross-section of a conductor in 1 second. What is the current flowing through the conductor?

Name two gases which are filled in filament type electric light bulbs.

Name two effects produced by electric current.

Name two devices which work on the heating effect of electric current.

Name the unit of electrical resistance and give its symbol.

Name the quantity whose unit is (i) kilowatt, and(ii) kilowatt-hour.

Name the physical quantity whose unit is “ohm”.

Name the material which is used for making the heating element of an electric iron.

Name the material which is used for making the filaments of an electric bulb.

Name the law which relates the current in a conductor to the potential difference across its ends.

Name the law which is illustrated by the above V-I graph.

Name the electrical property of a material whose symbol is “omega”.

Name the commercial unit of electric energy.

Name a device which helps to maintain potential difference across a conductor (say, a bulb).

Name a device that helps to measure the potential difference across a conductor.

Keeping the resistance constant, the potential difference applied across the ends of a component is halved. By how much does the current change?

Keeping the potential difference constant, the resistance of a circuit is halved. By how much does the current change?

In which direction does conventional current flow around a circuit?

In which direction do electrons flow?

If the potential difference between the end of a wire of fixed resistance is doubled, by how much does the electric power increase?

If the length of a wire is doubled by taking more of wire, what happens to its resistance?

If the current passing through a conductor is doubled, what will be the change in heat produced?

If 20C of charge pass a point in a circuit in 1s, what current is flowing?

How should the two resistances of 2 ohms each be connencted so as to produce an equivalent resistance of 1 ohm?

How much work is done when one coulomb charge moves against a potential difference of 1 volt?

How much work is done in moving a charge of 2C across two points having a potential difference of 12V?

How many milliamperes are there in 1 ampere?

How many microamperes are there in 1 ampere?

How do you think the brightness of two lamps arranged in parallel compares with the brightness of two lamps arranged in series (both arrangements having one cell)?

How does the wire in the filament of a light bulb behave differently to the other wires in the circuit when the current flows?

How does the resistance of a pure metal change if its temperature decreases?

How does the presence of impurities in a metal affect its resistance?

How does the heat H produced by a current passing through a fixed resistance wire depend onb the magnitude of current I?

How can you change the brightness of the lamps?

Explain why, filament type electric bulbs are not power efficient.

Draw a circuit diagram showing two lamps, one cell and a switch connected in series.

Draw a circuit diagram showing two electric lamps connected in parallel together with a cell and a switch that works both lamps. Mark an on your diagram to show where an ammeter should be placed to measure the current.

Define one coulomb charge.

Compare how an ammeter and a voltmeter are connected in a circuit.

Christmas tree lamps are usually wired in series. What happens if one lamp breaks?

By what other name is the unit joule/ coulomb called?

By what name is the physical quantity coulomb/ second called?

Are the lights in your house wired in series?

A resistance of 20 ohms has a current of 2 amperes flowing in it. What potential difference is there between its ends?

A potential difference of 20 volts is applied across the ends of a resistance of 5 ohms. What current will flow in the resistance?

An electric lamp is labelled 12V, 36W. This indicates that it should be used with a 12V supply. What other information does the label provide?

An electrician has wired a house in such a way that if a lamp gets fused in one room of the house, all the lamps in other rooms of the house stop working. What is the defect in the wiring?