Atomos Test Generator Free PYQs ExamsMy practice Log in / Sign up free

Units and Measurements

JEE Main 2025 (Online) 28th January Morning ShiftNumericalEasy📈 Topic in 34% papers+4
Ques. 1JEE Main 2025, 28 January (Morning Shift)

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 x100 where x is .

Answer

3

Solution

Least count = pitchno. of divisions = 0.7515 = 0.05 mm

l = b = 0.05 mm

A = lb AA = ll + bb

= 0.055 + 0.052.5 = 0.01 + 0.02 = 3100

x = 3

Answer: 3

Keep practising — Units and Measurements

Ques. 2JEE Main 2025, 28 January (Evening Shift)

Match List - I with List - II. Choose the correct answer from the options given below:

  1. (A)-(II), (B)-(I), (C)-(IV), (D)-(III)
  2. (A)-(I), (B)-(III), (C)-(IV), (D)-(II)
  3. (A)-(III), (B)-(I), (C)-(IV), (D)-(II)
  4. (A)-(III), (B)-(I), (C)-(II), (D)-(IV)
Ques. 3JEE Main 2025, 24 January (Morning Shift)

For an experimental expression y= 32.3 112527.4, where all the digits are significant. Then to report the value of y we should write

  1. y=1326.186
  2. y=1326.2
  3. y=1326.19
  4. y=1330
Ques. 4JEE Main 2025, 24 January (Morning Shift)

The least count of a screw gauge is 0.01 mm. If the pitch is increased by 75% and number of divisions on the circular scale is reduced by 50%, the new least count will be 10-3 mm.

Ques. 5JEE Main 2025, 24 January (Evening Shift)

The energy E and momentum p of a moving body of mass m are related by some equation. Given that c represents the speed of light, identify the correct equation

  1. E2=pc2+m2c4
  2. E2=pc2+m2c2
  3. E2=p2c2+m2c4
  4. E2=p2c2+m2c2
Ques. 6JEE Main 2025, 23 January (Morning Shift)

The position of a particle moving on x-axis is given by x(t)=A t+B 2t+Ct2+D, where t is time. The dimension of ABCD is

  1. L
  2. L3 T-2
  3. L2 T-2
  4. L2
Ques. 7JEE Main 2025, 23 January (Morning Shift)

The electric flux is = + where and are linear and surface charge density, respectively. ( ) represents

  1. displacement
  2. charge
  3. electric field
  4. area
Ques. 8JEE Main 2025, 23 January (Evening Shift)

The energy of a system is given as E(t)= 3e- t, where t is the time and =0.3 s-1. The errors in the measurement of and t are 1.2\% and 1.6\%, respectively. At t=5 s, maximum percentage error in the energy is :

  1. 6\%
  2. 11.6\%
  3. 4\%
  4. 8.4\%
Ques. 9JEE Main 2025, 23 January (Evening Shift)

Match List - I with List - II Choose the correct answer from the options given below :

  1. (A)-(III), (B)-(II), (C)-(IV), (D)-(I)
  2. (A)-(I), (B)-(IV), (C)-(II), (D)-(III)
  3. (A)-(II), (B)-(I), (C)-(III), (D)-(IV)
  4. (A)-(IV), (B)-(III), (C)-(I), (D)-(II)
Ques. 10JEE Main 2025, 22 January (Morning Shift)

If B is magnetic field and 0 is permeability of free space, then the dimensions of (B/ 0) is

  1. MT-2A-1
  2. L-1A
  3. ML2T-2A-1
  4. LT-2A-1
Ques. 11JEE Main 2025, 22 January (Morning Shift)

Given below are two statements : In the light of the above statements, choose the correct answer from the options given below.

  1. Both Statement I and Statement II are false
  2. Statement I is true but Statement II is false
  3. Both Statement I and Statement II are true
  4. Statement I is false but Statement II is true

All Units and Measurements PYQs →

PDFDownload Units and Measurements PYQs as PDF Free, with answer key and a QR code to every solution — print it or study offline⬇
All JEE Main Physics chapters