JEE Main · 2011 · 10 Apr 2011 · Offline · Units & Measurement

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A screw gauge gives the following reading when used to measure the diameter of a wire.

Main scale reading : 0 mm
Circular scale reading : 52 divisions
Given that 1 mm on main scale corresponds to 100 divisions of the circular scale.
The diameter of wire from the above date is :
  1. (A)0.052 cm✓ Correct
  2. (B)0.026 cm
  3. (C)0.005 cm
  4. (D)0.52 cm

Answer: (A)

Solution

The least count of the screw gauge is the pitch divided by the number of circular-scale divisions, . The main scale reads zero and the circular scale shows divisions, so the diameter is , which is .

JEE Main · 2011 · 10 Apr 2011 · Offline · Single correct option

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