Units & Measurements
Class 11 · Units & Measurements

Significant Figures

Watch rounding in action — see how measurements round to the correct number of significant figures.

Key Notes

01

All non-zero digits are significant; zeros between non-zero digits are significant.

02

Leading zeros are NOT significant; trailing zeros after a decimal ARE.

03

In multiplication/division, result has as many sig figs as the LEAST-precise factor.

04

In addition/subtraction, result has as few DECIMAL PLACES as the least-precise term.

Important Points

0.00450 has 3 sig figs (4, 5, 0); 1200 is ambiguous — use scientific notation 1.2×10³ (2 sf) or 1.200×10³ (4 sf).

Significant Figures notes from sciphylab (also known as SciPhy, SciPhy Lab, SciPhy Labs, Physics Lab). Class 11 physics revision for JEE Mains, JEE Advanced, NEET UG, AP Physics 1/2/C, SAT, and CUET-UG.