Science [4 Mark Questions]

Series circuit:

1. Same amount of current flows through all the components.
2. Voltage is different across different components.
3. Components are arranged in a line.
4. If one component breaks down, the whole circuit will bum out.

Parallel circuit:

1. The current flowing through each component combines to form the current flow.
2. Sum of the voltage through each component will be the voltage drawn from the source.
3. Components are arranged parallel to each other.
4. Other components will function even if one component breaks down.

1. Fuse:

1. Fuse is a strip of alloy wire which is made up of lead and tin with a very low melting point.
2. This can be connected to the circuit.
3. The fuse is usually designed to take specific amount of current.
4. When current passing through the wire exceeds the maximum limit, it gets heated up.
5. Due to low melting point, it melts quickly disconnecting the circuit. This prevents damage to the appliances.

2. Electric irons :

1. When current flows through the heating element, the heat energy developed is conducted to the heavy metal base, raising its temperature.
2. This energy is then used to press clothes.

1. Lightning arrestor is a device used to protect buildings from the effects of lightning.
2. Lightning conductor consists of a metallic lightning rod that remains in air at the top of the building.
3. Major portion of the metal rod and copper cable are installed in the walls during its construction.
4. The other end of the rod is placed deep into the soil.
5. When lightning falls, it is attracted by the metallic rods at the top of the building.
6. The rod provides easy route for the transfer of electric charge to the ground.
7. In the absence of lightning arrestors, lightning will fall on the building and the building will be damaged.

1. Charging:
Transfer of charge from one object to another is called charging. In case of the gold leaves charge is transferred through the brass rods.

2. Electrical Discharge:
The gold leaves resume their normal position after some time. This happens because they lose their charge. This process is called electrical discharge. The gold leaves would also be discharged when someone touches the brass rod with bare hands. In that case, the charge is transferred to the earth through the human body.

Structure of I metroscope :

1. It is made up of a glass jar.
2. A vertical brass rod is inserted into the jar through a cork.
3. The top of the brass rod has a horizontal brass rod or a brass disc.
4. Two gold leaves are suspended from the brass rod inside the jar.

Working of Electroscope:

1. When the brass disc of the electroscope is touched by a charged object, electric charge
2. gets transferred to the gold leaf through the rod.
3. This results in the gold leaves moving away from each other.
4. This happens because both the leaves have similar charges.