Exams › JEE Main › Physics
When both jaws of vernier callipers touch each other, zero mark of the vernier scale is right to zero mark of main scale. 4th mark on vernier scale coincides with certain mark on the main scale. While measuring the length of a cylinder, observer observes 15 divisions on main scale and 5th division of vernier scale coincides with a main scale division. Measured length of cylinder is ____ mm. (Least count of Vernier calliper = 0.1 mm)
- 15.4
- 15.1
- 15.5
- 15.9
Correct answer: 15.1
Solution
The measured length of the cylinder is calculated by adding the main scale reading (15 mm) to the value of the coinciding vernier scale division (0.1 mm for the 1st division, 0.2 mm for the 2nd, 0.3 mm for the 3rd, 0.4 mm for the 4th, and 0.5 mm for the 5th). Thus, the total length is 15 mm + 0.5 mm = 15.5 mm, but since the zero mark of the vernier scale is to the right of the main scale zero, we subtract the least count, resulting in 15.1 mm.
Related JEE Main Physics questions
- A body has a measured mass of \(5.00 \pm 0.05\) kg and a measured volume of \(1.00 \pm 0.05\) m\(^3\). What is the maximum possible percentage error in its density?
- A substance has a density of 4 g/cm\(^3\) in the CGS system. If a new unit system is used where the unit of length is 10 cm and the unit of mass is 100 g, what is the numerical value of the density in that system?
- Which of the following physical quantities has dimensions that do not match the other three?
- If the percentage uncertainties in measuring mass \(M\), length \(L\), and time \(T\) are 1%, 1.5%, and 3% respectively, what is the percentage error in a quantity having dimensions \(M L^{-1} T^{-1}\)?
- If \(E\), \(m\), \(J\), and \(G\) denote energy, mass, angular momentum, and the gravitational constant, respectively, then the dimensional formula of \(EJ^2/(m^5G^2)\) is identical to that of which quantity?
- A rod was found to have a measured length of 3.50 cm. Which measuring device was used for this reading?
⚔️ Practice JEE Main Physics free + battle 1v1 →