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A level physics

errors and uncertainty
1. For a cube of length 5.0+0.2cm and mass 500+1g ,calculate:
a)the percentage error in length
b)the percentage error in mass
c)the percentage error in volume
d)the percentage error in density
e)the fractional error in density
can someone help me with c,d and e ?

Reply 1

username3754758

c) v=a^3 with a being the length
so 0.2+0.2+0.2= 0.6/5 * 100 is ur percentage error
d) d=m/v
so using the answer to part c do 1/500 * 100 and divide the percentages
e) im not sure on that one

Reply 2

Physics Enemy

Original post by mia888

For a cube of length 5.0 +/- 0.2 cm and mass 500 +/- 1 g, calculate:

a) percentage error in length
b) percentage error in mass
c) percentage error in volume
d) percentage error in density
e) fractional error in density

Recommended post on this: https://www.thestudentroom.co.uk/showthread.php?t=2661762

a) L = 5.0 cm +/- 4% b) m = 500 g +/- 0.2%
c) V = L^3 = 125.0 cm^3 has % error 3*4 = 12%
d) ρ = m/V = 4.0 g/cm^3 has % error 0.2 + 12 = 12.2%
e) 12.2% as a fraction is (5*12.2)/(5*100) = 61/500