S.I unit of Luminous Intensity is

If input frequency of a full wave rectifier be n, then output frequency would be-

What is the audible frequency range?

What is the minimum distance required for an obstacle to produce a distinct echo?

Which atmospheric layer contains ozone layer?

What is the power of a lens whose focal length is 1 m?

Which law is also called the law of inertia?

Which of the following physical quantities is scalar quantity ?   

Which of the following instruments is correctly matched with its function?

I) Voltmeter - Measures potential difference