Question

The masses of two bodies are measured to be 15.7+_0.2 kg and 27.3 +_ 0.3 kg. what is the total mass of the two and the error in it

Answer 1

Answer:

The total mass = 43 kg

Error in total mass = 0.5 kg

Explanation:

If the masses of the bodies are m₁ and m₂ then error in the masses are respectively are

Δm₁ = 0.2

Δm₂ = 0.3

We know that if two quantities are X and Y and Z is a third quantity and the errors in X and Y are respectively ΔX and ΔY then the error in Z, ΔZ is given by

ΔZ = ΔX + ΔY

Therefore the error in the combined mass m is given by

Δm = Δm₁  + Δm₂

      = 0.2 + 0.3

      = 0.5

The total mass of the two = 15.7 + 27.3 = 43 kg

Hope this answer helps you.