Light year is used to measure
- distance between stars
- distance between atoms
- revolution time of earth around sun
- none of the above
The Correct Option is A
Solution and Explanation
Light year is an important unit of long distances (to measure the distance of stars, and terrestrial objects). One light year is the distance traveled by light in a vacuum in one year.
As velocity of light in vacuum is \(3 \times 10^{8} ms ^{-1}\) and \(1\) year \(=365 \times 24 \times 60 \times 60\) second,
Therefore, 1 light \(=3 \times 10^{8} \times(365 \times 24 \times 60 \times 60)\) metre
\(\therefore 1\) light year \(=9.46 \times 10^{15} m\)
A light-year is a measurement of distance and not time (as the name might imply). A light-year is a distance a beam of light travels in a single Earth year, which equates to approximately 6 trillion miles (9.7 trillion kilometers).
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Concepts Used:
Physical World
The physical world includes the complications of the natural world around us. It is a type of analysis of the physical world around us to understand how it works. The fundamental forces that control nature are:
- Gravitational Force is a universal force that exists as an outcome of mutual attraction between any two objects with respect to their masses.
- Electromagnetic Force can be understood as the force that is present between the charged particles. The force is stated by Coulomb’s law.
- Strong Nuclear Force is the force that ties the protons and neutrons in a nucleus. Of all the elemental forces in nature, a strong nuclear force is the strongest as its name suggests.
- Weak Nuclear Force can only be noticed in some of the nuclear processes such as the beta decay of the nucleus.