Question

Which if, any, of these statements are true? (More than one may be true.) Assume the batteries are ideal. 

 Check all that apply. 

•  A battery supplies the energy to a circuit. 

•  A battery is a source of potential difference; the potential difference between the terminals of the battery is always the same. 

•  A battery is a source of current; the current leaving the battery is always the same.

Answer 1

Concepts and reason

The concepts required to solve the question is of battery connected in the circuit, charge and current.

Initially, in the 1^st option, explain the role of battery in the circuit and then state whether the statement is true or false.

In the 2^nd statement, explain the potential difference, and then explain the potential difference between the terminals of a battery.

Finally, in 3^rd sentence, explain the concept of current leaving the battery.

Fundamentals

A battery is the source that supplies energy in the circuit. Batteries lift charges to a higher potential.

There is a potential difference in a circuit because each coulomb of charge has a different potential energy.

Battery is a source of energy. Current is induced in the circuit because of the movement of charge with respect to time. Current is mathematically given by,

Here, q is the charge, i is the current, and t is the time.

(a)

A battery connected in the circuit provides the energy for the flow of charge from the higher potential to the lower potential.

Thus, battery supplies the energy to a circuit.

(b)

The battery is a source of energy, which in turn introduce the potential difference between the two terminals. So, if the emf, i.e. voltage is applied by the battery itself, the potential difference between the terminals of the battery is always the same.

So, a battery is a source of potential difference; the potential difference between the terminals of battery is always the same is true.

[Part b]

Part b

Part b

(c)

A battery provides the energy in the circuit. So, battery is a source of energy, not the current. It can be easily seen by the equation of current. It is given by,

Here, battery, which can be denoted by V, is not in the equation of the formation of current. Thus, battery is not a source of current, but it is a source of energy. Also, current leaving the battery will not be the same always.

Ans: Part a

The battery supplies the energy to a circuit is true.

Part b

A battery is a source of potential difference; the potential difference between the terminals of battery is always the same is true.

Part c

A battery is a source of current; the current leaving the battery is always the same is

false.