JEE-Main - Grade 11 - Physics - Units and Measurements - Importance and Snapshot of Unit And Measurements - Study ref# 697

Introduction:
Measurement of any physical quantity involves comparison
with a certain basic, arbitrarily chosen, internationally accepted reference
standard called unit. The result of a measurement of a physical
quantity is expressed b... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Importance and Snapshot of Unit And Measurements - Study ref# 698

Following sections must be covered to understand Unit and
Measurements:
1. Introduction
2. The international system of units
3. Measurement of length
4. Measurement of mass
5. Measurement of time
6. Accuracy, precision of inst... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Target Setup for Unit And Measurements - Study ref# 699

Student requires to achieve the following milestones to get better grip over Unit and Measurements. The milestones / targets are as follows:- Starting Point: Days 0Test TypeAppear on TestTarget TestsScorePractice Test000%Chapter ... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 1

Write the dimension of the following: 1. Angle 2. Torque 3. Relative Density 4. Spring factor 5. Strain Answer: 1. Angle = 2. Torque =3. Relative Density = 4. Spring factor = 5. Strain = ... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 2

A drop of olive oil of radius 1mm spreads into a circular film of diameter 40 cm on water surface. Estimate the size of an oil molecule. Answer: Volume should be conserved. Radius of olive oil R = 1mm. Radius of oil after spread ... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 3

The Sun’s angular diameter is measured to be 1920''. The distance D of the Sun from the Earth is m. What is the diameter of the Sun? Answer: Sun’s angular diameter = 1920'' Sun’s diameter ... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 4

The unit of length convenient on the nuclear scale is a fermi. . Nuclear sizes obey roughly the following empirical relation: where r is the radius of nucleus, A its mass number and r0 is a constant equal to about 1.2 fermi. S... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 5

A physical quantity Q is given by The percentage error in A, B, C, D are 1%, 2%, 4%, 2% respectively. Find the percentage error in Q. Answer: Percentage of error in ... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 6

What is 1 AU? 1 Au is equal to how much metre? Answer: 1 AU:The average distance between the Sun and the Earth is called 1 AU or 1 Astronomical Unit.1 AU = = 1.496 × 1011 m... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 7

Name two physical quantities whose dimensions are same. Answer: Stress and Young’s modulus or, Work and Energy.... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 8

Name at least seven physical quantities whose dimensions are ML2T-2. Answer: 1. Pressure energy 2. Potential energy 3. Kinetic energy 4. Work 5. Torque 6. Momentum of Force and 7. Couple... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 9

If where x is the length and t is time, then find dimensional formula for Answer: ... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 10

The length, breadth and thickness of a metal sheet are 4.454 m, 1.015 m, and 2.02 cm respectively. Give the area and the sheet to correct significant figures. Answer: The thickness has three (minimum) significant figures.Now, the total surface area o... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 11

The length and breadth of a rectangular area are 25.2 cm and 16.8 cm respectively and have been measured to an accuracy of 0.1 cm. Find the percentage error in the area. Answer: Percentage of error Percentage of error &nbs... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 12

While measuring the volume of a sphere an error of 1.2% is committed in the measurement of radius. What percentage error is introduced in the measurement of volume? Answer: where is a constant. It is easy to say that Devid... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 13

The time of oscillation (t) of a small drop of liquid under surface tension depends upon the density ρ, radius r and surface tension σ.Prove dimensionally that Answer: Time of oscillation where k is constant.Writi... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 14

Liquid is flowing through steadily through a pipe. Assume that the volume of the liquid flowing out per second depends on (a) The coefficient of the viscosity of the liquid η (b) The radius of the pipe r (c) The pressure gradient a... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 15

Show dimensionally that the frequency n of transverse waves in a string of length l and mass per unit length m under a tension T is given by Answer: Let us suppose that, where K is a dimensionless constant and a, b, c are... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 16

If the length and time period of an oscillating pendulum have errors of 1% and 2% respectively, what is the error in the estimate of g? Answer: We have, Percentage of error in g = 1 + 2 x 2 = 5%... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 17

A physical quantity P is related to four observable a, b, c and d as follows: The percentage error of measurement in a, b, c and d are 1%, 3%, 4%, 2% respectively. What is the percentage error in the quantity P? If the value of P calcul... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 18

The volume V of a cylinder of diameter d and height h is given by Both the diameter of the cylinder and its height are measured using a metre scale having a least count of 0.1 cm. Find the percentage error in the measurement of V if d = 1.... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 19

State equation for 1 mole real gas is: where P is the gas pressure, V is the volume of gas and T is absolute temperature of gas and are constant. Find the dimension of Answer: From of the principle of homogeneity of dimension... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 20

Two resistance are connected in series. Find the equivalent resistance. Also find the percentage error in calculating equivalent resistance. Answer: So The percentage error in equivalent resistance is... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 21

What is 1 parsec? Compute its value into meter. Answer: 1 parsec: It is the distance at which 1 AU would subtend an angle of 1 arcsec.1 parsec = Now 1 AU = 1.496 × 1011 m... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 22

The equation of a wave is given by , where is the angular velocity and v is the linear velocity. What will be the dimension of k? Answer: From the homogeneity principle of dimension... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 23

Define light year. Find its value in meter unit. Answer: Light year: 1 light year is the distance that light travels with velocity3 × 108 ms-1 in 1 year.So, 1 light year = &nb... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 24

Find out the dimension of Plank’s constant. Answer: We know the energy of a wave with frequency is , where h is the plank’s constant.So, ... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 25

Find the dimensional formula for Young’s modulus. Answer: Young’s modulus Now ... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 26

The centripetal force on a particle is of the form . Find the values of Answer: The equation is given by So, Equating the powers of similar quantities we get,So, ... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 27

Check whether the equation Answer: The equation has three quantities. If the dimension of all three quantities are identical then the equation is correct.Now, So, all three quantities have same dimension i.e. Therefore, the given equa... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 28

The amount of heat transferred per second through two opposite surface of a rectangular slab is governed by the equation where A is the cross sectional area and d is the separation between two opposite surfaces and T1, T2 are the temp... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 29

In a simple pendulum experiment, a student took several data for the time period of oscillation. His readings are 2.64 s, 2.78 s, 2.71 s, 2 68 s, 2 75 s. Find i) mean period of oscillation, ii) absolute error in each reading, iii) mean absolute error... read more

JEE-Main - Grade 11 - Physics - Units and Measurements - Study ref# 30

Three physical quantities X, Y and Z have units . What will be the relation between X,Y and Z? Answer: Let, , where k is a dimensionless quantity and a, b are any numbersAccording to question, Putting the dimensi... read more