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The rod in a gold leaf electroscope is made up of brass.

When the charges are not allowed to flow are termed as static electricity, i.e., the electricity at rest.

A lightning conductor is made up of copper.

EFFECTS OF LIGHTINING: Lightning can kill the men, animals and shatter the buildings.

(d) The assertion is false but reason is true

Rubbing certain materials with one another can cause the built-up of electrical charges on the surfaces. So charges are produced by friction.

Example: Combing hair charges are transferred from the hair to comb due to friction.

Electrical Earthing is defined as the process of transferring the discharge of electrical energy directly to the Earth With the help of low resistance wire.

The process of transferring of charge from a charged object to the earth is called earthing.

Earthing is the process of connecting the exposed metal parts of an electrical circuit to the ground.

The path through which electrons flow from one terminal to another terminal of the source, is called electric circuit.

The process of depositing a layer of one metal over the surface of another metal by passing electric current is called electroplating.

Electro plating is applied in many fields: 

1. We use iron in bridges and automobiles to provide strength. 

2. A coating of zinc is deposited on iron to protect it from corrosion and formation of rust. 

3. Chromium has a shiny appearance. It does not corrode. 

4. It resists scratches

Transfer of charges takes place in the following three ways: 

1. Transfer by Friction 

2. Transfer by Conduction 

3. Transfer by Induction

1. Transfer by Friction: This method of charging an uncharged body by rubbing it ; against another body is called charging by friction. 

Example: While combing hair charges are transferred from the hair to comb due to friction.

2. Transfer by conduction: Charges can be transferred to on object by bringing it in contact with a charged body. This method of transferring charges from one body to other body is calledtransfer by conduction. 

Example: When the ebonite rod is rubbed with woollen cloth, electrons from the woollen cloth are transferred to the ebonite rod. Now ebonite rod will be negatively charged.

(i) When it is brought near the paper cylinder, negative charges in the rod are attracted by the positive charges in the cylinder. 

(ii) When the cylinder is touched by the rod, some negative charges are transferred to the paper. Hence, the negative charges in the rod are repelled by the negative charges in the cylinder.

3. Transfer by Induction: The process of charging an uncharged body by bringing a charged body near to it but without touching it is called induction. 

Example: we can charge an uncharged object when we touch it by a charged object. But, it is also possible to obtain charges in a body without any contact with other charges.

The correct option is D) Mobiles.

1. Wiser? I kilo watt is used per one hour, it Is considered as 1 kilo watt hour (KWH) 

2. 1 KWH = 1 UNIT of electricity.

1. If we connect batteries/cells in series it enhance the brightness of the bulb, the batteries in a torch light are connected in series. 

2. So, to enhance the brightness of the bulb.

Kilo watt hour (or) UNIT.

i) If a number of cells are connected in series the brightness of the bulb is enhanced, 

ii) If a number of cells are connected in parallel the brightness of the bulb remains same (or) does not change.

1. MCB means Miniature Circuit Breaker. 

2. It is being used in place of electric fuses. 

3. There is a switch which automatically turns off when electricity in circuit exceeds the safe limit. 

4. So, the circuit is opened. 

5. We just need to switch ON to resume electric supply. 

6. At present MCB is available with automatically resumed built-in mechanism. 

7. MCB is better than electric fuses. 

8. There is no need to change it often. 

9. But fuse wire has to be changed whenever it melts. 

10. Hence, I appreciate the MCB for protecting home appliances.

Electricity supplied to our houses comes ban the power stations and substations.

1. If all the first terminals of all the devices are connected to one point and all the second terminals are connected to another point such type of connection is called parallel connection. 

2. In parallel connection electricity has more than one path. 

3. Even if any one of them is removed the circuit remains closed.

The correct option is D) above all.

The correct option is A) Enhanced.

Lithium ion cells are rechargeable and are used in mobile phones, laptops etc.

The correct option is B) Only one path.

1. If the second terminal of the first device is connected to the first end of the second device, such type of connection is called series connection. 

2. In series connection electricity has only one path. 

3. If any of them is removed or not functioning properly, it becomes an open circuit.

The correct option is C) As usual.

Button cells are used in wrist watches, laser lights. thermometers (electronic), computers etc.

The correct option is B) Parallel.

Switch is used to open or dose a circuit.

The parallel connection of cells, increases the battery life.

In our daily life we use different types of bulbs. Some of them are Incandescent bulb, fluorescent both (tube light). CFL (Compact Fluorescent Lamp), LED bulb etc.

Solution : 

Given, Q = 20 C, t=1s I=? 

We know that: 

I=Q/t. I=20/1=20A

Given, Q = 20 C, t = 1s I =?

We know that: I = Q/t.

I = 20/1 = 20A

(a) electrons; closed

(b) amperes; ammeter; series.

Given, Q = 20 C, t = 1s I = ?

We know that:

I = Q/t. 

Thus I = 20/40 = 0.5A.

True

The flow of charge through a conducting wire connected to a cell is the result of chemical reaction inside the cell.

Given, I = 4amp, C, t = 10s Q = ?

We know that:

I = Q/t. Q = 4*10 = 40C.

True

Electric bulb works on heating effect of current.

False

Current is the amount of charge flowing per unit time.

i = \(\frac{q}{t}\)

True

Power is given by,

I = P/V =2000/220 = 9.09 A

No, we cannot run.

Current needed is more than 5 A