In mechanics, matter waves or de Broglie waves reflects the wave–particle duality of matter. The de Broglie relations show that the wavelength is inversely proportional to the momentum of a particle and is also called de Broglie wavelength.

Correct Option: A

In mechanics, matter waves or de Broglie waves reflects the wave–particle duality of matter. The de Broglie relations show that the wavelength is inversely proportional to the momentum of a particle and is also called de Broglie wavelength.

The twinkling of stars and variation in size of the Sun are due to atmospheric refraction of light. Besides, refraction is also responsible for the sun to look during sunset and sunrise. It is also responsible for the sun becoming two or three minutes before actual sunrise. The sun appears higher or lower in the sky due to the changing position of the Earth relative to the Sun.

Correct Option: C

The twinkling of stars and variation in size of the Sun are due to atmospheric refraction of light. Besides, refraction is also responsible for the sun to look during sunset and sunrise. It is also responsible for the sun becoming two or three minutes before actual sunrise. The sun appears higher or lower in the sky due to the changing position of the Earth relative to the Sun.

A neuron is a nerve cell that is the basic building block of the nervous system. Neurons are specialized to transmit infor-mation throughout the body. These highly specialized nerve cells are responsible for communicating information in both chemical and electrical forms.

Correct Option: D

A neuron is a nerve cell that is the basic building block of the nervous system. Neurons are specialized to transmit infor-mation throughout the body. These highly specialized nerve cells are responsible for communicating information in both chemical and electrical forms.

A Sonometer is a device for demonstrating the relationship between the frequency of the sound produced by a plucked string, and the tension, length and mass per unit length of the string. These relationships are usually called Mersenne's laws after Marin Mersenne (1588-1648), who investigated and codified them.

Correct Option: D

A Sonometer is a device for demonstrating the relationship between the frequency of the sound produced by a plucked string, and the tension, length and mass per unit length of the string. These relationships are usually called Mersenne's laws after Marin Mersenne (1588-1648), who investigated and codified them.

The Electromagnetic spectrum in order of decreasing energy, thus increasing wavelength : Gamma Rays– wavelength: 0.01 nm ; X-rays –1 nm ; Ultra-violet Rays-0.1 micrometres ; Visible LightRed light : 0.7 micrometres, Violet Light : 0.4 micrometres ; Infrared Radiation–0.01 mm ; Microwaves -less than 10 cm, usually 1cm ; Radiowaves- Long, Medium and Short Waves : 2 km-10 m ; and Very High Frequency (VHF) and Ultra High Frequency (UHF): 10 m–10 cm.

Correct Option: D

The Electromagnetic spectrum in order of decreasing energy, thus increasing wavelength : Gamma Rays– wavelength: 0.01 nm ; X-rays –1 nm ; Ultra-violet Rays-0.1 micrometres ; Visible LightRed light : 0.7 micrometres, Violet Light : 0.4 micrometres ; Infrared Radiation–0.01 mm ; Microwaves -less than 10 cm, usually 1cm ; Radiowaves- Long, Medium and Short Waves : 2 km-10 m ; and Very High Frequency (VHF) and Ultra High Frequency (UHF): 10 m–10 cm.