Name: Conversion of Units Using Dimensional Analysis
Uploaded: 2019-07-19
Duration: 6 min 14 s
Description: How do you solve problems if the units of quantity are different? Is there any conversion method? Let us discuss the conversion using dimensional analysis in this video.

Question

(i) How many significant figures are there in the following quantities ?
(a) $10.163,$
(b) $1.67 \times 10^{- 17},$
(c) $0.270,$
(d) $1.496,$
(e) $15000,$
(f) $2.4300,$
(g) $0.001040$

(ii) Round off the following numbers to three significant figures.
(a) $3.264,$
(b) $0.9462,$
(c) $1.667,$
(d) $1.285,$
(e) $45.875$

Accepted Answer

(i) (a) $10.163,$ : All non-zero digits and the zeroes lying between two non-zero digits are significant. Hence, five significant figures.

(b) $1.67 \times 10^{- 17},$ : All digits lying in a base number of a scientific notation are significant.
Hence, three significant figures.

(c) $0.270$ : In a number having decimal point, trailing zeroes are significant, but zeroes in the beginning are not significant. Hence, three significant figures.

(d) $1.496$ : Four significant figures.

(e) $15000$ : In a number without a decimal point, trailing zeroes are not significant.
Hence, two significant figures.

(f) $2.4300$ : Five significant figures.

(g) $0.001040$ : Four significant figures.

(ii) (a) $3.264 \to 3.26$ : As $1.667,$ , preceding digit will be unchanged.

(b) $1.285,$ : As $2 < 5$ , preceding digit will be unchanged.

(c) $1.667 \to 1.67$ : As $7 > 5$ , preceding digit will be increased by $1$ .

(d) $1.285 \to 1.28$ : As the number is $5$ , preceding digit can not be changed.

(e) $45.875 \to 45.9$ : As $7 > 5$ , preceding digit will be increased by $1$ .

Important Questions on Units and Measurements

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(i) How many significant figures are there in the following quantities ? (a) 10.163, (b) 1.67×10-17, (c) 0.270, (d) 1.496, (e) 15000, (f) 2.4300, (g) 0.001040 (ii) Round off the following numbers to three significant figures. (a) 3.264, (b) 0.9462, (c) 1.667, (d) 1.285, (e) 45.875

Important Questions on Units and Measurements

Learn and Prepare for any exam you want !