Physics (Part-2) (CDS-Solved Paper)

When the person approaches the mirror by 40 cm.
Then, the new distance of the person from the mirror is
x = 100 cm − 40 cm = 60 cm
∴ Distance between the person and his image is
d = 2x = 2 × 60 = 120 cm = 1.2m

In a dry cell, chemical energy is converted into electrical energy. Electrons are generated due to chemical reaction inside a dry cell that is responsible for the flow of current.

A bi-focal lens consists of both concave and convex lenses. The upper portion consists of a concave lens which facilitates the distinct vision while the lower part is convex lens which facilitates the nearby vision.

Tungsten is uniquely suitable for using as a filament in electric bulbs because of its high melting point (3695 K), so that it can withstand larger temperature without melting.

Inactive nitrogen and argon gases are usually used in electric bulbs in order to increase the life of the filament. As the gases, chamber cannot be filled with air that contain oxygen because it will cause the filament to burn, i.e. react with oxygen.

White light constitutes of seven colours. Wavelength of violet coloured light is least and wavelength of red is maximum. In this given diagram shown below, violet light refracted the most, while red light least. Refractive index of material of the prism will be maximum for violet coloured light and it will be minimum for red coloured light because refractive index is inversely proportional to the wavelength of light.
Higher the refractive index of a material lesser will be the speed of light in this material. Therefore, violet light of shortest wavelength will have least speed that is retarded.

An oscilloscope is an instrument which allows us to see sound waves which are longitudinal waves in nature.

As the graph is parallel to time axis, therefore the object is at rest because position remains unchanged. If the object is moving with uniform speed, then the graph is given by
If the object is moving with non-linear motion, then the graph is given by
If the object is moving with non-uniform motion, then the graph may be given by
Hence, option (b) is correct.

For a harmonic oscillator, velocity is maximum at mean position and minimum at extreme points. Also, velocity varies non-uniformly between mean position and extreme position. This leads to an elliptical graph between velocity and displacement. Therefore, momentum and displacement graph will also be elliptical.