JEE Main202528 Jan 2025Morning ShiftPhysicsExperimental PhysicsActual
A tiny metallic rectangular sheet has length and breadth of 5 mm and 2.5 mm , respectively. Using a specially designed screw gauge which has pitch of 0.75 mm and 15 divisions in the circular scale, you are asked to find the area of the sheet. In this measurement, the maximum fractional error will be x 100 where x is _________.
Correct answer
0
Step-by-step solution
Since least count of the instrument can be calculated as aligned & Least count = pitch length No. of division on circular scale & = 0.75 15 =0.05 ~mm . aligned Here we are provided L =5 ~mm & ~W =2.5 ~mm L =5 ~mm & ~W =2.5 ~mm We know that A = L . W For calculating fractional error, we can write dA ~A = dL ~L + dW ~W Here dL = dW =0.05 ~mm aligned & dA ~A = 0.05 5 + 0.05 2.5 & dA ~A = 1 100 + 2 100 = 3 100 aligned So, x=3