Question

You measure two quantities as A = 1.0 m ± 0.2 m, B = 2.0 m ± 0.2 m. We should report correct value for √AB as: (a) 1.4 m ± 0.4 m (b) 1.41m ± 0.15 m (c) 1.4m ± 0.3 m (d) 1.4m ± 0.2 m

Answer 1

Here,
a=(1.0±0.2)m
b=(2.0±0.2)m
ab=(1.0*2.0)±(0.2*0.2)
=(2.0±0.4)m²
√ab=√(3.0±0.4)m²
=(1.4±0.2)m
hence option D is correct.
hope this will help you..