If 'm' is the mass, 'c' is the velocity of light and x = mc2, then dimensions of 'x' will be:
Correct answer: B. [ML2T-2]
- A. [LT-1]
- B. [ML2T-2]
- C. [MLT-1]
- D. [MLT-2]
Explanation
The equation x = mc² represents the relationship between mass and energy, where x is the energy equivalent of a mass m, and c is the speed of light.To determine the dimensions of x, we need to consider the dimensions of each variable in the equation. The dimensions of mass are [M], the dimensions of the speed of light are [LT-1].Using the rules of dimensional analysis, we can find the dimensions of x by substituting the dimensions of m and c into the equation and simplifying:x = mc²= [M][LT-1]²= [M][L2T-2]Therefore, the dimensions of x are [ML2T-2], which is option B.
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Classical physics cannot explain blackbody radiation and related observations, leading to Planck’s quantum theory, in which energy is emitted or absorbed in discrete packets. Photons provide the particle model of light, with energy and momentum linked to frequency and wavelength, including the photoelectric effect and its threshold frequency.
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