Question

the main scale reading while measuring the thickness of a small spherical object using a vernier calliper is 5cm and the vernier scale coincidence is 9 if the vernier calliper shows a negative 0 error off-0.07 find the radius of the spherical object

Answer 1

ANSWER

Least count ,LC=1MSD−1VSD

Here 10VSD=9MSD or 1VSD=(9/10)MSD

Thus, LC=(1−9/10)1MSD=1/10×0.1cm=0.01cm  (as 1MSD=0.1cm from diagram)

From diagram, main scale reading, MSR=4.3cm and vernier scale reading, VSR=7(because division 7 coincide with any line on main scale )

The diameter of the metal ball =MSR+(VSR×LC)=4.3+(7×0.01)=4.37 cm

Radius of the ball =4.37/2=2.185 cm=2.18 cm