Electric Current

Q. An electric fuse can prevent accidents arising from

1. An overload but not due to short circuit.
2. A short circuit but not due to overload.
3. An overload as well as short circuit.
4. Neither an overload nor a short circuit.

Q. Which one of the following is the property of a monochromatic, plane electromagnetic wave in free space ?

​​​​​​​$[$1 Mark$]$

1. Electric and magnetic fields have a phase difference of $\frac{\pi }{2}$.
2. The energy contribution of both electric and magnetic fields are equal.
3. The direction of propagation is in the direction of $\overrightarrow{B}\times \overrightarrow{E}$
4. The pressure exerted by the wave is the product of its speed and energy density.

Q.

Electricity is not a form of energy.

1. False

2. True

Q.

​What will happen if the guy in our example, who picks up balls from below and puts it on top of the C-shaped tube, stops doing his job?

1. The balls will have no one to pick them up, the current will stop.

2. The current will be there even without him doing anything.

3. The balls will start going backwards.

4. None of these

Q.

Electrons are _____ particles.

1. neutral

2. positively charged

3. negatively charged

4. current

Q.

Electricity is very essential for our day to day activities.

1. True

2. False

Q.

Which of the following particle is responsible for the electric current in a wire?

1. Neutron

2. Positron

3. Proton

4. Electron

Q.

Electric current is said to be the flow of _____.

1. Electrons

2. Both A and C

3. Protons

4. Neutrons

Q.

An electric current is said to be flowing through a wire when:

1. Neutrons pass through it

2. Electric charges pass through it

3. No particle passes through it

4. Only tennis balls pass through it

Q. In an electric current, at any given point of time, all the electrons will be moving in the same direction.

1. Yes

2. Not every time, but definitely sometimes.