⚛️ Physics · Units and Measurements · NEET & JEE

A physical quantity X is given by X = (P²Q<sup>1/2</sup>)/(R³S²), where P, Q, R, S are measured with percentage errors of 3%, 2%, 1%, and 4% respectively. The percentage error in X is:

Answer: 18%.

A 18%
B 10%
C 8%
D 20%

Correct answer: A. 18%

Explanation: Using the power rule, %error in X = 2(3%) + (1/2)(2%) + 3(1%) + 2(4%) = 6 + 1 + 3 + 8 = 18%.

The 7 SI base units. All derived units (newton, joule, watt, volt, etc.) can be expressed as combinations of these 7 fundamental units raised to various powers.

Concept context

SI base units, dimensional analysis, significant figures, and error propagation. The toolkit every physics calculation relies on.

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A physical quantity X is given by X = (P²Q<sup>1/2</sup>)/(R³S²), where P, Q, R, S are measured with percentage errors of 3%, 2%, 1%, and 4% respectively. The percentage error in X is:

Concept context

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