Tag: physics

Questions Related to physics

What is advantage of primary cell over secondary cell

physics current electricity electric cells and batteries

  1. Its internal resistance is low

  2. It is light and cheap

  3. It can provide low/high currents

  4. It is rechargable

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Correct Option: B
Explanation:

Primary cells are light and cheap. All other options apply to secondary cell.

Primary cells are

physics current electricity electric cells and batteries

  1. Recyclable

  2. Use and throw

  3. Rechargable

  4. Retractable

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Correct Option: B
Explanation:

Primary cells are use and throw. They are not recyclable since structure is carefully packed. They are not rechargable since chemical reactions involved are not recyclable. 

Primary cells have _____ resistance and secondary cells have ______ resistance

physics current electricity electric cells and batteries

  1. Low , High

  2. High, Low

  3. Low , Low

  4. High , High

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Correct Option: B
Explanation:

Primary cells have high internal resistance while secondary cells have low internal resistance.

Secondary cells are called

physics current electricity electric cells and batteries

  1. Condensors

  2. Accumulators

  3. Distributors

  4. Assimilators

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Correct Option: B
Explanation:

Secondary cells are also called accumulators.

Which one of the following primary cells has emf 1.08 volts and which remains fairly constant?

physics current electricity electric cells and batteries

  1. Daniel cell

  2. Simple voltaic cell

  3. Leclanche cell

  4. Dry cell

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Correct Option: D
Explanation:

Dry cell have a typical voltage of around 1.1 Volts.They become inadequate for use with time because their internal resistance increases many fold.

The primary cell which is used in daily life is-

physics current electricity electric cells and batteries

  1. Leclanche cell

  2. Dry cell

  3. Daniel cell

  4. Simple voltaic cell

Show answer
Correct Option: B
Explanation:

Commonly used cell is dry cell.

Dry-cell is essentially comprised of a metal electrode or graphite rod {elemental carbon} surrounded by a moist electrolyte paste enclosed in a metal cylinder. in most common type of dry cell battery the cathode u=is composed of a form of elemental carbon called graphite.

The current capacity of the charged secondary cell does not depend on ?

physics current electricity electric cells and batteries

  1. rate of charging

  2. rate of discharging

  3. temperature

  4. amount of active material

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Correct Option: C
Explanation:

The current capacity of the charged secondary cell does not depend on temperature. so if the temperature is increased or decreased there is no any change in current capacity of any secondary cell, hence option C is correct.

Cell which cannot be charged is 

physics current electricity electric cells and batteries

  1. Primary cell

  2. Secondary cell

  3. Electrochemical cell 

  4. None of the above 

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Correct Option: A
Explanation:

A primary cell cannot be charged whereas secondary and electrochemical cell can be recharged.charging of a cell depends upon cell reaction is either reversible or irreversible . when reaction is irreversible then cell can not be charge after one time discharge.

When two batteries are connected in series the voltage in the circuit will _____________ .

physics current electricity and magnetism electric cells and batteries

  1. increase

  2. decrease

  3. remains same

  4. first decrease than increase

Show answer
Correct Option: A
Explanation:

In a series connection the positive terminal of the first battery is connected to the negative terminal of the second battery.

And the Equivalent voltage of the battery is the sum of the voltage of individual cell.So, when two batteries are connected in series the voltage in the circuit will increases.
Therefore, A is correct option.

Choose the wrong option

physics current electricity and magnetism electric cells and batteries

  1. A cell is a single unit which converts chemical energy to electrical energy to deliver a voltage while a battery is composed of a number of cells in series to get increased voltage

  2. A Battery is a single unit which converts chemical energy to electrical energy to deliver a voltage while a cell is composed of a number of batteries in series to get increased voltage

  3. In the combination of cells, cells are connected in such a way that negative terminal of a cell is connected to positive terminal of the next cell

  4. In the combination of cells, cells are connected in such a way that negative terminal of a cell is connected to negative terminal of the next cell

Show answer
Correct Option: B,D
Explanation:

Both cell and battery store the chemical energy and then transforms the stored chemical energy to electrical energy. But cell is a single unit with positive and negative terminal whereas battery is a combination of cells connected end to end i.e. positive  to negative terminal.