The retina is the thin light-sensitive membrane lining the inner eyeball-towards the back of the eye. As our eye lens are convex in nature, they form mostly real and inverted images on the retina. When the images formed are real and inverted, the message sent by the optic nerve are chemical impulses which turn them into erect images that we see.

Correct Option: A

The retina is the thin light-sensitive membrane lining the inner eyeball-towards the back of the eye. As our eye lens are convex in nature, they form mostly real and inverted images on the retina. When the images formed are real and inverted, the message sent by the optic nerve are chemical impulses which turn them into erect images that we see.

The boiling point is the temperature at which the vapour pressure of the liquid equals the environmental pressure surrounding the liquid. Atmospheric pressure is due to air above any given point. The atmospheric pressure at high altitudes like hill station is less than at the sea level.Thus, vapour pressure will equal atmospheric pressure at a comparatively low temperature. Thus, the boiling point of water is reduced less than at sea level.

Correct Option: B

The boiling point is the temperature at which the vapour pressure of the liquid equals the environmental pressure surrounding the liquid. Atmospheric pressure is due to air above any given point. The atmospheric pressure at high altitudes like hill station is less than at the sea level.Thus, vapour pressure will equal atmospheric pressure at a comparatively low temperature. Thus, the boiling point of water is reduced less than at sea level.

According to Rayleigh’s law, the intensity of scattered light varies inversely as the fourth power of its wavelength. Sunlight consists of seven colours. Of these, red has the maximum wavelength. During sunrise and sunset, the rays have to travel a larger part of the atmosphere because they are very close to the horizon. Therefore, light other than red is mostly scattered away. Most of the red light, which is the least scattered, enters our eyes. Hence, the sun and the sky appear red.

Correct Option: D

According to Rayleigh’s law, the intensity of scattered light varies inversely as the fourth power of its wavelength. Sunlight consists of seven colours. Of these, red has the maximum wavelength. During sunrise and sunset, the rays have to travel a larger part of the atmosphere because they are very close to the horizon. Therefore, light other than red is mostly scattered away. Most of the red light, which is the least scattered, enters our eyes. Hence, the sun and the sky appear red.

If there is no gravity, there will not be any upward thrust to keep a liquid buoyant. Whenever a body is placed in a fluid, the fluid applies resultant up ward directional force on the body and it is called up thrust. It’s numerical value which is the product of volume of the fluid displaced, density of the fluid and acceleration due to gravity at the given place. Up thrust increases with increase in acceleration due to gravity and vice versa.

Correct Option: D

If there is no gravity, there will not be any upward thrust to keep a liquid buoyant. Whenever a body is placed in a fluid, the fluid applies resultant up ward directional force on the body and it is called up thrust. It’s numerical value which is the product of volume of the fluid displaced, density of the fluid and acceleration due to gravity at the given place. Up thrust increases with increase in acceleration due to gravity and vice versa.

A spring scale or spring balance or Newton meter is a type of weighing scale. It consists of spring fixed at one end with a hook to attach an object at the other. It works by Hooke’s Law, which states that the force needed to extend a spring is proportional to the distance that spring is extended from its rest position.

Correct Option: B

A spring scale or spring balance or Newton meter is a type of weighing scale. It consists of spring fixed at one end with a hook to attach an object at the other. It works by Hooke’s Law, which states that the force needed to extend a spring is proportional to the distance that spring is extended from its rest position.