Which of the following is the most precise device for measuring length :
(a) a vernier callipers with 20 divisions on the sliding scale
(b) a screw gauge of pitch 1 mm and 100 divisions on the circular scale
(c) an optical instument that can measure length to within a wavelength of light ?

Which of the following is the most precise device for measuring length (i) a vernier calipers with 20 divisions on the sliding scale (ii) a screw gauge of pitch Imm and 100 divisions on the circular scale (iii) an optical instrument that can measure length to within a wavelength of light?

Which of the following is the most precise devise for measuring length ? (a) a Vernier callipers with 20 divisions on the sliding scals, coindiing with 19 main scale divions (b) a screw gauge of pitch 1mm and 100 divisions on the circular scale (c ) an optical instrument that can measure length to within a wave length of light.

Which of the following is the most precise device for measuring length ? (a) a vernier calliper with 20 divisions on the sliding scale, coinciding with 19 main scale divisions (b) a screw gauge of pitch 1mm and 100 divisions on the circular scale (c ) an optical instrument that can measure length to within a wavelength of light.

which of the following devices is more precise ? a) a vernier callipers with 10 divisons on the sliding scale b) a screw guage of pitch 1 mm and 100 divisos on the circular scale .