Frank solutions for Class 9 Physics ICSE chapter 8 - Electricity and Magnetism [Latest edition]

State the kind of charge on a positive ion.

State the kind of charge on a negative ion.

The following Figure represents a negatively charged gold Ieaf electroscope. Label the parts, P, Q, and R and the estate whether each is an insulator or a conductor. Also, indicate the distribution of charges on the system in the diagram.

The following figure shows a metal rod PQ mounted on an insulated stand. The cap of an uncharged electroscope touches one end Q of the metal rod. A negatively charged ebonite rod is brought near the other end P of the metal rod.

(a) What charge does the end P have?
(b) What charge does the end Q have?
(c) What charge does the cap of the electroscope have?
(d) What charge does the gold leaf have?
(e) Will the leaf diverge or collapse? Give reason.
(f) If the electroscope is now earthed, what charge does the metal rod have?

What do you mean by an electric current?

What is an electric cell? 

Name the constituents of a cell. 

Write SI unit of
Electric current,

Write SI unit of
Potential difference

Write SI unit of
Resistance.

What is the number of electrons that would flow per second through the cross-section of a wire when 1 A current flows in it?

0.7 C charges passes through a cross-section of a conductor in 7 s. Find the current.

Name the instrument used to control current in an electric circuit.

What is the other name of a variable resistor?

What is the function of a switch in an electric circuit?

Write symbol and state function of following component in an electric circuit :

cell

Write symbol and state function of following component in an electric circuit :

ammeter

Write symbol and state function of following component in an electric circuit :

voltmeter

Write symbol and state function of following component in an electric circuit :

rheostat

A current of 1.2 A flows through a conductor for 3.0 s. What amount of charge passes through the conductor?

Label the different parts A, B, C, D, E, and F. State the functions of each part. Show in the diagram the direction of flow of current.

l-V graph is shown for a good conductor. What does the slope of the graph represent?

What do you mean by the potential difference? Write its SI unit.

Is electric current a scalar quantity?

State the factors on which the electrical resistance of a wire depends.

What is the SI unit of resistance?

A bulb is connected to a cell. How is the resistance of circuit affected if another identical bulb is connected (i) in series, (ii) in parallel, with the first bulb?

'The resistance of a wire is 2 ohm'. Explain the meaning of this statement.

Write symbol and state function of following component in an electric circuit :

cell

Write symbol and state function of following component in an electric circuit :

ammeter

Write symbol and state function of following component in an electric circuit :

voltmeter

Write symbol and state function of following component in an electric circuit :

rheostat

State three factors on which the resistance of a wire depends. Explain, how does the resistance depend on the factors stated by you.

What amount of work is required in moving 3 C charge through a potential difference of 6 V?

What is the physical meaning of resistance?

A wire of resistance 1 Ω is stretched to double its length. What will happen to the resistance of the stretched wire?

Explain the following:
Potential difference

Explain the following:
Open circuit

Explain the following:
Closed circuit

Compare the brightness of two 60 watt bulbs.
When they are connected in series.
Explain giving scientific reasons.

Compare the brightness of two 60 watt bulbs.
 When they are connected in parallel.
Explain giving scientific reasons.

Differentiate between:
Conductors and insulators.

Differentiate between:
Flow of electron and flow of conventional current.

Suggest the best particles in the use of energy at school.

Suggest the best particles in the use of energy at home that save energy.