WORKSHEET
1. The sides of a rectangle are (10.5 ± 0.2) cm and (5.2 ± 0.1) cm. Calculate its perimeter with error limits. (Ans. (31.4 ± 0.6) cm)
2. If displacement of a body s = (200 ± 5) m and time taken by it t = (20 +0.2) s, then
find the percentage error in the calculation of velocity. (Ans. 3.5%)
3. A physical quantity is measured as Q = (2.1 ± 0.5) units. Calculate the percentage error in
(a) Q2 (b) 2Q. (Ans. 48% and 24% ) Solution
4.The length of a rod as measured in an experiment was found to be 2.48m, 2.46m, 2.49m, 2.50m and 2.48m. Find the average length, absolute error and percentage error. Express the result with error limit. (Ans. 2.48 ± 0.01)m (2.48m ± 0.40%)
5. The error in the measurement of radius of a sphere is 2%. What would be
the error in :
(a) Volume of sphere
(b) Surface area of sphere. (Ans. 6% and 4% )
6. The value of two resistors are R1 = (6 ± 0.3) Ω
and R2 = (10± 0.2) Ω. Find the percentage error in the equivalent
resistance when they are connected in parallel. (Ans. 10.125% ) Solution
7. The mass and the volume of a body are found to be 5.00 ± 0.05 kg and 1.00 ± 0.05 m3 respectively. What is the maximum possible percentage error in its density. (Ans. 6%)
8. What are the number of significant figures for the numbers 23.023 , 0.0003 and 2.1 x 10-3 ?
9. The refractive index (μ) of water is found to have the values 1.29, 1.33, 1.34, 1.35, 1.32, 1.36, 1.30 and 1.33. Calculate the mean value, absolute error, the relative error and the percentage error. (Ans. 1.33 , 0.02 , 0.02, ± 1.5 %)
10. A current of 3.5 ± 0·5 ampere flows through metallic conductor. And a potential difference of 21 ± 1 volt is applied. Find the Resistance of the wire. (Ans. R = 6 ± 1.14 Ω )