The human eye is sensible to light wave which wavelength is roughly between 400 nm and 700 nm. When illumination is enough (in daylight) the maximum sensitivity is in the green region at 555 nm.

Correct Option: B

The human eye is sensible to light wave which wavelength is roughly between 400 nm and 700 nm. When illumination is enough (in daylight) the maximum sensitivity is in the green region at 555 nm.

A compound microscope is a microscope which uses multiple lenses to collect light from the sample and then a separate set of lenses to focus the light into the eye or camera. The objective lens provides the primary magnification which is compounded (multiplied) by the ocular lens (eyepiece).

Correct Option: B

A compound microscope is a microscope which uses multiple lenses to collect light from the sample and then a separate set of lenses to focus the light into the eye or camera. The objective lens provides the primary magnification which is compounded (multiplied) by the ocular lens (eyepiece).

The sunlit sky is blue because air scatters shortwavelength light more than longer wavelengths. Since blue light is at the short wavelength end of the visible spectrum, it is more strongly scattered in the atmosphere than long wavelength red light. The result is that the human eye perceives blue when looking toward parts of the sky other than the sun.

Correct Option: C

The sunlit sky is blue because air scatters shortwavelength light more than longer wavelengths. Since blue light is at the short wavelength end of the visible spectrum, it is more strongly scattered in the atmosphere than long wavelength red light. The result is that the human eye perceives blue when looking toward parts of the sky other than the sun.

The outside surface of a utensil used for heating is coated black so that it may absorb more heat and make heating quicker. This is because black surface is a good absorber of heat.

Correct Option: D

The outside surface of a utensil used for heating is coated black so that it may absorb more heat and make heating quicker. This is because black surface is a good absorber of heat.

The lower atmosphere is more or less transparent to radio waves. However, the ionosphere reflects back the radio waves. Thus, a signal emitted by an antenna from a certain place can be received at another place on the surface of Earth in the following two ways: ground wave propagation and sky wave propagation.

Correct Option: C

The lower atmosphere is more or less transparent to radio waves. However, the ionosphere reflects back the radio waves. Thus, a signal emitted by an antenna from a certain place can be received at another place on the surface of Earth in the following two ways: ground wave propagation and sky wave propagation.