Experiments Questions and Answers

The Binding energy per nucleon of 3Li and He nuclei are 5 60 MeV and 7 06 MeV respectively In the nuclear reaction Li H He He Q the value of energy Q released is 1 19 6 MeV 3 8 4 MeV AIPMT 2014 2 2 4 MeV 4 17 3 MeV

8 When two resistances R 2 0 0 1 22 and R 1 0 0 1 are connected in series the effective value of their resistance Ris a 3 0 0 1 b 3 0 0 2 79 c 3 0 0 070 In the above problem the maximum error in measuring R is d 1 99

No work is done by a force on an object if a the force is always perpendicular to its velocity b the force is always perpendicular to its acceleration c the object is stationary but the point of application of the force moves on the object d the object moves in such a way that the point of application of the force remains fixed

If an object at absolute temperature 7 radiates energy at rate R then select correct graph showing the variation of log R with log 7 Assume log e o A 0 1 2 log R log R V 3 log 7 log R log 7 log 7 log R I 4

3 stationary wave 4 none of the above A screen is placed 90 cm from an object The image of an object on the screen is formed by a convex lens at two different locations separated by 20 cm The focal length of the lens is 1 18 cm 2 21 4 cm 3 60 cm 4 85 6 cm

The radius of a sphere is measured to be 7 50 0 85 cm Suppose the percentage error in its volume is x The value of x to the nearest x is Given wer

of a system of three particles of masses 1g 2g and 4g is taken as the origin of a coordinate system The position vector of a fourth particle of mass 7g such that the centre of mass of the four particle system lies at the point 2 3 4 is a 21 31 4k where a is a constant The value of a is 1 2 2 1 2 3 3 2 4 15 Bullets of ma gun with au the bullet then th 1 30 3 5 2 Centre of mass for uniform half ring and uniform half disc will be respectively at following distance from their centre 16

COMPONENT CO2 H2S N C C MW SG 0 03 0 02 0 05 0 775 0 086 0 025 0 003 0 004 0 002 0 005 120 0 7 Rock Properties 0 2 0 15 30 Acre 20 ft If the reservoir pressure and temperature are 3500 psia and 165 F calculate the Gas recovery factor RF at 2500 and 1500 psi

a 15 4 A UHF television loop antenna has a diameter of 11 cm The magnetic field of a TV signal is normal to the plane of the loop and at one instant of time its magnitude is changing at the rate 0 16 T s The magnetic field is uniform What emf is induced in the antenna a 1 52 x 10 3 V b 0 35 x 10 2 V c 0 54 x 10 y b 10 J c 20 J d 10 5 J

E A student measures the time period of 100 oscillations of a simple pendulum four times That data set is 90 s 91 s 95 s and 92 s If the minimum division in the measuring clock is 1 s then the reported mean time should be 2006 a 92 5 0s b 92 1 8s c 92 3s d 92 2s

Example 7 7 The angular speed of a motor wheel is increased from 1200 rpm to 3120 rpm in 16 seconds i What is its angular acceleration assuming the acceleration to be uniform ii How many revolutions does the engine make during this time

The Gravitron single car roller coaster has a loop the loop that is constructed so that riders on the coaster will feel perfectly weightless when they reach the top of the circular arc How heavy will they feel when they reach the bottom of the arc that is what is the normal force pressing up into their seats a the bottom of the loop Assume that the arc is perfectly circular and no frictional forces act on the car Assume that the mass of rider is m Two blocks of masses m 5kg and m 2 kg hang on either side of a frictionless cylinder as in Fig If the system starts at rest what is the speed of m after it has fallen 105 cm m O m

2 0 f a Z b Choose the correct statement 1 both a and b depend on the target material 2 both a and b are independent of the target material 3 both a and b depend on the energy of the electron beam 1 K 4 a is dependent on the target material dont of target material

5 A student measures the distance traversed in free fall of a body initially at rest in a given time He uses this data to estimate g the acceleration due to gravity If the maximum percentage errors in measurement of the distance and the time are e and e respectively the maximum percentage error in the estimation of g is 2 e 202 4 e 2e 1 e e fo

126 For the logic circuit shown the truth table is A B 1 3 4 D A 0 0 1 1 A 0 0 1 1 A 0 0 1 1 A 0 0 1 1 BY 0 1 1 0 1 1 1 BY 1 1 1 0 BY 0 1 0 0 0 Y 0 0 0 1 0 1 0 1 0 1 B 0 1 0 1 1000 Y

What is the angle between A and the resultant it Branded

a 1 875 atm b 0 2155 atm 0 4618 atm 1 A fresh radioactive mixture contains short lived species A and B Both emitting a particles initially of 8000 a particles per minute 20 minutes later they emits at the rate of 3500 a particles per minute If the half lives of the species A and B are 10 minutes and 500 hours respectively then the ratio of activities of A B in the initial mixture was a 4 6 b 6 4 c 3 4 d 3 1 imple of solution of 10

xample 4 olution In a circular vernier callipers value of 1 MSD is 1 and 30th vernier division coincide with 29th M calculate least count of instrument 30 VSD 29 MSD 29 x 1 1 VSD 29 30 L C of vernier 1 29 30 1 2

79 How many minimum NAND gets will be required to represent the boolean expression Y ABC 1 2 8 2 3 3 4 4 5

initial velocity of a particle moving along straight line with constant acceleration is 20 2 m s i its acceleration is a 5 0 1 m s2 then velocity of particle with error after time t 10 1 s is 1 70 3 1 m s 2 70 2 m s 3 70 4 m s 4 70 8 m s

a 0 15 gram b 0 135 gram 9 A silver coin weighing 11 34 g was dissolved in nitric acid When sodium chloride was added to the solution all the silver present as AgNO3 was precipitated as silver chloride The mass of the precipitated silver chloride was 14 35 g Calculate the percentage of silver in the coin a 4 8 b 95 2 c 90 d 80 and V at mass 14 combine to form compounds A B and C The

A solid horizontal surface is covered with a thin layer of oil A rectangular block of mass m 0 4 kg is at rest on this surface An impulse of 1 0 Ns is applied to the block at time t 0 so that it starts moving along the x axis with a velocity v t ve where vo is a constant and t 4 s The displacement of the block in meters at t Tis Take e 0 37 2018 3 7

If X 8 00 0 04 cm and Y 4 00 0 04 cm X Y then should be expressed as 1 2 00 0 01 2 2 00 0 02 3 2 00 0 03 4 2 00 0 04

3 Blocks A and B kept on a smooth horizontal surface are given equal speeds of 2 m s in opposite sense as shown in the figure I Ap 2 m s 4 kg 2 m s 2 4 kg origin 4 5 m 0 At t 0 the position of blocks are shown then the coordinates of Centre of mass of system of two blocks at t 3s will be 1 1 0 3 5 0 2 3 0 4 2 25 0 28 The r 29 a mas 51 3 1 2 3 0 9 A bom 4 kg a 24 m s 1 192 3 576

3 1 20 4 1 25 3 A freely falling body takes 4s to reach the ground One second after release the percen tage of its initial potential energy that is still retained is 1 6 25 3 37 5 A body of mass 2 25 4 93 75 is proiected vertica

4 l A student performs an experiment for determination of g T Al A 5 mm B 5 mm C 5 mm D 1 mm error of Al For T he takes the time of n oscillations with the stop watch of least count AT and he commits a human error of 0 1sec For which of the following data the measurement of g will be most accurate 2006 AT 0 2 sec 0 2 sec 0 1 sec 0 1 sec n 10 20 20 50 l 1m and he commits an Amplitude of oscillation 5 mm 5 mm 1 mm 1 mm

Two measurement are as A 2 00 0 01 cm ar B 1 00 0 01 cm The AB is given as 1 2 00 0 01 cm 2 2 00 0 15 cm 3 2 00 0 03 cm 4 2 0 01 cm

6 Two force vectors F and F each of magnitude 10 N act at a point at an angle of 60 The magnitude of resultant force vector is 1 10 N 2 10 3 N 4 20 3 N 3 20 N

33 A great physicist of this century P A M Dirac loved playing with numerical values of Fundamental constants of nature This led him to an interesting observation Dirac found that from the basic constants of atomic physics c e mass of electron mass of proton and the gravitational constant G he could arrive at a number with the dimension of time Further it was a very large number its magnitude being close to the present estimate on the age of the universe 15 billion years From the table of fundamental constants in this book try to see if you too can construct this number or any other interesting number you can think of If its coincidence with the age of the universe were significant what would this imply for the constancy of fundamental constants

44 A transistor cannot be used as a 1 Amplifier 2 Oscillator 3 Modulator 4 Rectifier

When a magnet is pushed in and out of a circular coil C connected to a very sensitive galvanometer G as shown in the adjoining diagram with a frequency then N S 1 Constant deflection is observed in the galvanometer 2 Visible small oscillations will be observed in the galvanometer if is about 50 Hz 3 Oscillations in the deflection will be observed clearly if or 2 Hz 4 No variation in the deflection will be seen if or 2 Hz

units find the value of the current at t 5 s An electron gun emits 2 0 10 An electron gun emits 2 0 x 10 16 electrons per second What electric current does this correspond to

An ideal monostomic gas is confined in a horizontal cylinder by a spring loaded piston as shown in figure Initially the gas is at temperature T pressure P and volume V and the spring is in its felax state the gas is then heated very slowly to temperature T pressure P and volume V During m process the piston moves out by a distance x Ignoring the friction between the piston and the cylinds the correct statement s is are JEE Advanced 2015 P 2 4 88 23 A IT V 2V and T 3T then the energy stored in the spring is P V B If V 2V and T 3T then the change in internal energy is 3P V C IV 3V and T 4T then the work done by the gas is D If V 3V and T 4T then the heat su the gas is 17 RY

inch 8 In a vernier callipers main scale divisions are in inches Each inch division has eight small divisions of each 8 divisions of vernier scale are equal to 7 divisions of main scale While measuring the length of a rod callipers shows the reading as follows What is the length of rod A 75 64 inch 77 C 64 inch B 76 64 inch D None of these 1 inch www 2 Vernier scale Main scale

The value of e me can be obtained by using a specially designed vacuum tube The figure contains a heated filament F and an anode A which is maintained at a positive potential relative to the filament by a battery of known voltage V Electrons get emitted from the heated filament and are accelerated towards the anode which has a small hole in the centre for the electrons to pass through into a region of constant magnetic field B which points into the plain of the paper The electrons then move in a semicircle of diameter d hitting the detector cathode as shown Prove that me 8V B d B F d

5 A physical quantity X is related to four measurable quantities a b c and d as given X a2 b c5 2 d 2 The percentage error in the measurement of a b c and d are 1 2 2 and 4 respectively What is the percentage error in quantity X a 15 b 17 c 21 d 23

The displacement of an oscillating particle is given by x asinot bcos t where a b and are constants Prove that the particle performs a linear S H M with amplitude A a b 2

A student performs experiment with simple pendulum and measures time for 10 vibrations If he measures the time for 100 vibrations the error in the measurement of time period will be reduced by a factor of a 10 b 90 c 100 d 1000

of error measurement of physical quantities A B C and D are 1 2 3 and 4 respectively Then the maximum percentage of error in the measurement X 2 bns A B 2 2 where Y will be In an experiment the percentage occurred in the

Suppose all the electrons of 100 g water are lumped together to form a negatively charged particle and all the nuclei are lumped together to form a positively charged particle If these two particles are placed 10 0 cm away from each other find the force of attraction between them Compare it with your weight

X HP N vin Y Bar magnet Poles of magnet

Regular Medical 2 a point has simultaneous velocities represented by u 2u 3 3u and 4u The angle between the first and second the second and third and the third and fourth are respectively 60 90 and 150 The angle the resultant velocity makes with u is 1 120 2 60 3 150 4 30 14

INTRODUCTORY EXERCISE 3 4 1 A student performs an experiment to determine Young s modulus of a wire exactly 2 m long by Searle s method In a particular reading the student measures the extension in the length of the wire to be 0 8 mm with an uncertainty of 0 05 mm at a load of 1 0 kg The student also measures the diameter of the wire to be 0 4 mm with an uncertainty of 0 01 mm Take of elasticity with limits of error

If P Q R 0 PI 2 Q1 and R 2121 then the angle between R and P is 1 COS 3 tan 1 5 4 2 1 2 2 4 sin 1 tan 3 4 2 5 4 2

31 For two resestors R and R connected in parallel if R 30 1 and R 60 2 The N percentage error in the measurement of equivalent resistance is 1 3 33 2 33 3

2 A body is simultaneously given two velociti one 12 ms due East and other 5 ms 1 North Find the resultant velocity

One centimeter of main scale of a vernier caliper is divided into 10 equal parts M S R and V C D observed while measuring the length of an object are 3 and 4 respectively Then the length of the object is number of division on vernier scale as 10 mm Take a 4 3 b 3 4 c 3 04 d 4 03

when used to measure the diameter of a wire Main scale reading 0 mm Circular scale reading 52 divisions Given that 1 mm on main scale corresponds to 100 divisions of the circular scale The diameter of wire from the above data is 1 2 3 0 52 cm 0 052 cm 0 026 cm

A funnel is placed upside down on a table as shown in the figure and 600 cm of water is poured into it The area covered by the funnel on the tabletop is 200 cm and the height of the water is 18 cm What is the minimum mass of the funnel in kg if it is not to be lifted away from the supporting surface 200 cm 18 cm

In determination of acceleration due to gravity g using the formula T 2 the errors in g measurement of L and T are 1 and 2 respectively The maximum percentage error in the value of g is 1 5 3 3 2 4 4 1 5