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Experimental Physics

JEE Main level, numerical answer, medium

33 of 70

Question 33 of 70

A student in the laboratory measures thickness of a wire using screw gauge. The readings are $1.22mm,1.23mm,1.19mm$ and $1.20mm$ . The percentage error is $\dfrac{x}{121}%$ . The value of $x$ is _____ .

Show answer and solution

Answer: 150

The average value of the readings is

{x}_{avg}=\dfrac{1.19+1.20+1.22+1.23}{4}=1.21

Now, absolute error in measurement

\Delta {x}_{avg}=\dfrac{0.02+0.01+0.01+0.02}{4}=\dfrac{0.06}{4}=0.015

Percentage error in measurement is

=\dfrac{0.015}{1.21}\times 100%

=\dfrac{150}{121}%

So, the value of

x=150

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JEE Main Physics practice question on Experimental Physics (Experimental Physics), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.

A student in the laboratory measures thickness of a wire using screw gauge. The readings are 1.22mm,1.23mm,1.19mm1.22mm,1.23mm,1.19mm1.22mm,1.23mm,1.19mm and 1.20mm1.20mm1.20mm. The percentage error is x121\dfrac{x}{121}%121x​. The value of xxx is _____ .

JEE Main question paper PDF

More Physics practice

A student in the laboratory measures thickness of a wire using screw gauge. The readings are $1.22mm,1.23mm,1.19mm$ and $1.20mm$ . The percentage error is $\dfrac{x}{121}%$ . The value of $x$ is _____ .