Fuse Wire

Q. Birds do not get electric shocks even if they are on a high voltage wire because:

1. They have high resistance in their body.
2. There is zero potential difference between any two points in their body
3. Their body parts are made of insulators.
4. Inside of their bodies there are very high voltages.

Q.

Fuse wire is made up of an alloy of ?

Q.

Why is the fuse wire fitted in a porcelain casing?

Q. A 1 km long voltage transmission line has a voltage 400 volts. If the current carrying wire has resistance 0.2 $\Omega$/meterthen how much electrical energy(in joules) will be lost in 0.5 seconds through the whole transmission line?

1. 400

Q.

Two resistors when connected in parallel give resultant value of $2\Omega$, when connected in series the value becomes $8\Omega$ , the resistance of each resistor is

1. 5Ω, 3Ω

2. 2Ω, 6Ω

3. 4Ω, 4Ω

4. 7Ω, 1Ω

Q. An electric fuse has a:

1. High resistance and High melting point
2. High resistance and Low melting point
3. Low resistance and High melting point
4. Low resistance and Low melting point

Q. Which of the following characteristics is NOT suitable for a fuse wire?

1. Low melting point
2. Connected in parallel in a circuit
3. Safety device
4. Circuit breaker

Q. An engine uses 720 KJ of energy in 2 hours. Calculate total electricity charges(in rupees) in two hours at a rate of 2.5 rupees per kWh?

1. 0.5

Q. A current of 6 A flows through the heater when the electric heater is connected to 120 V supply.How much heat will it generate if the same heater is connected to 220 V supply for 10 second?

1. 12.1 kJ
2. 24.2 KJ
3. 18.3 KJ
4. 30.4 KJ

Q. Assertion :It is advantageous to transmit electric power at high voltage. Reason: High voltage implies high current.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. Which of the following are the characteristics of a fuse wire?

1. Low melting point
2. Connected in parallel in a circuit
3. Safety device
4. Circuit breaker

Q.

The commercial unit of electrical energy is ___________.

Q. A group of N cells whose emf varies directly with the internal resistance as per the equation $E_n$= 1.5 $r_N$are connected as shown in the figure below. The current I in the circuit is

1. 0.51 amp
2. 5.1 amp
3. 1.5 amp
4. 0.15 amp

Q. Conceptual Questions
Why is it possible for a bird to sit on a high-voltage wire
without being electrocuted?