Tag: electric current, potential difference and resistance

Quizzes (6) Questions (109)

Questions Related to electric current, potential difference and resistance

Multiple choice physics electric current, potential difference and resistance electric potential and potential difference potential difference current in electric circuits

Name the physical quantity of which the unit is ampere: 

  1. Current.

  2. Capacitance

  3. Charge

  4. Voltage
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

An electric current is a flow of electric charge. In electric circuits this charge is often carried by moving electrons in a wire. It can also be carried by ions in an electrolyte, or by both ions and electrons such as in a plasma.
The SI unit for measuring an electric current is the ampere, which is the flow of electric charge across a surface at the rate of one coulomb per second. Electric current is measured using a device called an ammeter.

Multiple choice physics electric current, potential difference and resistance electric potential and potential difference potential difference current in electric circuits

In an electric circuit, current starts from the-

  1. Positive terminal

  2. Either of the two terminals

  3. Negative terminal

  4. Depends upon the circuit
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The direction of an electric current is by convention the direction in which a positive charge would move. Thus, thecurrent in the external circuit is directed away from the positive terminal and toward the negative terminal of the battery. Electrons would actually move through the wires in the opposite direction.

Multiple choice physics electric current, potential difference and resistance electric potential and potential difference potential difference current in electric circuits

The speed at which the current travels in a conductor, is nearly

  1. $3 \times 10^0 ms^{-1}$

  2. $3 \times 10^5 ms^{-1}$

  3. $4 \times 10^6 ms^{-1}$

  4. $3 \times 10^8 ms^{-1}$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Current travels in a conductor at a speed approximately equal to speed of light i.e. $3\times 10^8$ $ms^{-1}$.

Multiple choice physics electric current, potential difference and resistance electric potential and potential difference potential difference current in electric circuits

Which of the following statements is true?

  1. Electricity can be created

  2. Electricity flows in a circuit with gaps

  3. Electricity is the flow of negative charge

  4. All of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

(A) Option:- Electricity can be created. This statement is false because electricity is basically a form of energy that cannot be created nor be destroyed 


(B) Option:- Electricity flows in a circuit with gaps. This statement is false because electricity does not flow in open circuit.


(C) Option:- Electricity is the flow of negative charges.T his statement is true because due to the flow of electrons electricity is generated electrons are negatively charged.

Multiple choice physics electric current, potential difference and resistance electric potential and potential difference potential difference current in electric circuits

In a cell, electrons move from:

  1. positive electrode to negative electrode.

  2. negative electrode to positive electrode.

  3. both A and B.

  4. electrons do not move and only negative charge moves from one place to another place.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In cells, electrons move from negative electrode to positive electrode and an electron has negative charge. So, we can say that negative charge flows from negative electrode to positive electrode. But, by convention flow of charges are measured only through positive charges.When an electron moves from point A to point B,an equal amount of positive charge moves from point B to point A.

So, the direction of charge is from positive electrode to negative electrode. As unlike charges attract each other and like charges repel each other, thus electrons move from negative electrode to positive electrode inside a cell.

Multiple choice physics electric current, potential difference and resistance electric potential and potential difference potential difference current in electric circuits

In electrolysis:

  1. positive ions move toward the positive electrode and negative ions toward the negative electrode.

  2. positive ions move toward the negative electrode and negative ions toward the positive electrode.

  3. both ions move toward both the electrodes in equal amounts until they are balanced.

  4. none of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

As unlike charges attract each other and like charges repel each other. Thus in electrolysis, positive ions move towards the negative electrode whereas negative ions move toward the positive electrode.Hence option B is correct.

Multiple choice physics electric current, potential difference and resistance electric potential and potential difference potential difference current in electric circuits

The direction of current is taken as

  1. The opposite to the direction of flow of current.

  2. Opposite to the direction of flow of protons.

  3. Opposite to the direction of flow of electrons.

  4. All
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Conventionally, the direction of current is taken as the direction of flow of positive charge (protons) and opposite to the direction of flow of negative charge (electrons).
Hence option C is correct.

Multiple choice physics electric current, potential difference and resistance electric potential and potential difference potential difference current in electric circuits

In a DC circuit when a switch is closed to operate the circuit, the electrons that cause the current:

  1. travel from the negative plate of the battery to the positive plate

  2. travel from the positive plate of the battery to the negative plate

  3. travel from one resistance to the next resistance

  4. travel from the negative plate of the battery to the positive plate inside the battery

  5. travel from one atom in the circuit to the next atom
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In a DC circuit , when switch is closed , the free electrons in wire are drifted from negative plate of the battery to positive plate.