JEE Main 202623 JanuaryMorning Shift
- Exam
- JEE Main
- Year
- 2026
- Date
- 23 January
- Shift
- Morning Shift
- Subject
- Physics
- Chapter
- Experimental Physics
JEE Main 2026 · 23 January · Morning Shift · Physics · Experimental Physics
In a screw gauge, the zero of the circular scale lies 3 divisions...
In a screw gauge, the zero of the circular scale lies 3 divisions above the horizontal pitch line when their metallic studs are brought in contact. Using this instrument thickness of a sheet is measured. If pitch scale reading is 1 mm and the circular scale reading is 51 then the correct thickness of the sheet is mm.
[Assume least count is 0.01 mm ]
[Assume least count is 0.01 mm ]
Options
- A
- B
- C
- D
Correct answer
C.
Step-by-step solution
For a screw gauge, the measurement formula is: Reading = Pitch scale + (Circular scale × Least count) - Zero error
The zero of circular scale lies 3 divisions above the pitch line, indicating negative zero error:
Zero error = -3 × 0.01 = -0.03 mm
Reading = 1 + (51 × 0.01) - (-0.03) = 1 + 0.51 + 0.03 = 1.54 mm
The zero of circular scale lies 3 divisions above the pitch line, indicating negative zero error:
Zero error = -3 × 0.01 = -0.03 mm
Reading = 1 + (51 × 0.01) - (-0.03) = 1 + 0.51 + 0.03 = 1.54 mm