Physics (AS & A Level) · May / June 2018 · Paper 13 · Question 5

In an experiment to determine the Young modulus E of the material of a wire, the measurements taken are shown. mass hung on end of wire m = 2.300 ± 0.002 kg original length of wire l = 2.864 ± 0.005 m diameter of wire d = 0.82 ± 0.01 mm extension of wire e = 7.6 ± 0.2 mm The Young modulus is calculated using E = \frac{4mgl}{\pi d^2 e} where g is the acceleration of free fall. The calculated value of E is 1.61 × 10^{10} N m^{-2}. How should the calculated value of E and its uncertainty be expressed?

1. A(1.61 ± 0.04) × 10^{10} N m^{-2}
2. B(1.61 ± 0.05) × 10^{10} N m^{-2}
3. C(1.61 ± 0.07) × 10^{10} N m^{-2}
4. D(1.61 ± 0.09) × 10^{10} N m^{-2}

As printed in the paper