Physics

Problem

Three lengths are measured as

L_1=2.875\,\text{mm}

L_2=4.2\times10^{-4}\,\text{m}

, and

L_3=5.0\times10^{-2}\,\text{cm}

. Calculate

L_1-L_2+L_3

and give the result in metres, rounded to three significant figures and expressed in scientific notation. a)

2.95\times10^{-3}\,\text{m}

3.80\times10^{-3}\,\text{m}

2.96\times10^{-3}\,\text{m}

2.96\times10^{-4}\,\text{m}