Question

Choose the correct option in each of the following:

Which of the following is the unit of frequency?

• A. Metre
• B. Per metre
• C. Second
• D. Hertz

Answer 1

The correct option is D

Hertz

Explanation of the correct option:

Option (D):

Frequency:

1. It is defined as the number of vibrations in 1 second.
2. Hertz (Hz) is the SI measurement unit of frequency
3. For example, two complete waves pass through a point in 1 second. So, the frequency of the given wave is 2 Hz.

Explanation of the incorrect option:

Option (A):

Metre:

1. The path or gap that lies between two points is called length. Length is a scalar quantity.
2. Its SI measurement unit is metre (m).

Option (B):

Per metre:

1. Actually, per metre is not any measurement unit of any physical quantity.
2. For example, the standard unit of electric field strength is the volt per metre (V/m). An electric field of 1 V/m is represented by a potential difference of 1 V existing between two points that are 1 m apart.

Option (C):

Second:

1. The SI unit of the time period is second.
2. Time period is defined as the time taken for one complete vibration to pass through a given point. It is denoted by T.

So, the correct answer is option (D).