Question

Lamps used for street lighting are connected in
A.Parallel
B.Series and parallel both
C.Series
D.None of the above

Answer 1

Hint: This question can be easily solved by understanding the properties of both series and parallel connections. So if one is aware of the properties of both series and parallel connection one can easily solve this problem. To solve this question first, state the properties of both the connections, and then by comparing the properties one can easily determine the answer.

Complete answer:
Series connection: In a series connection, all the electrical components are arranged in a line. The amount of current that flows through each component in a series connection is the same.
In a series connection, when the resistors are arranged in a line the amount of voltage that flows through each resistor differs from the other. However, the amount of current that flows through each component is the same.
Another important point in a series connection is that if one component breaks down then the entire circuit will not work.
Parallel connection: In a parallel connection, all the electrical components are arranged in parallel to one another. The amount of current that flows through each component adds up to form the current flow through the source.
In a parallel connection, when the resistors are parallel to each other, the amount of voltage that flows through each resistor is the same.
Another important point in a parallel connection is that even if one component breaks down the other components in the circuit will function. As in a parallel connection, each has its independent circuit.
From the characteristics mentioned of both the series and parallel connection, we can conclude that lamps that are used to light up the streets are connected in parallel. It is in parallel connection as the voltage across each component is the same and also if one component breaks down, the other components will continue to work.
A.This is the correct option.
B.This is not the correct option as the components are connected only in parallel form.
C.The lamps are connected in parallel form and not in series. Therefore this is also the wrong option.
From the above discussion, we can conclude that the lamps are connected in parallel

Option A is the correct answer.

Note:
To calculate the resistance in a series connection, one has to just sum the values of the individual resistances. In a parallel connection, one must take the sum of the reciprocal of individual resistances and then find the reciprocal of the value. In this way for both series and parallel connection one can determine the equivalent resistance of the circuit.