Basic Physics Questions and Answers

A glass tube 80cm long and open at both ends is half immersed in mercury Then the top of the tube is close and it is taken out of the mercury A column of mercury 20cm long then remains in the tube The atmospher pressure in cm of Hg is 1 50 2 60 3 70 4 80

the switch is made closed the current induced in the circuit is X X 1 X 2 X X A D Bolv R X 3Bolv R 2Bolv X X X R wwww X X X X X X X B C X X Bo X X X X

straight lin 4 parabolic A long hollow tube is carrying an electric 3 urrent along its length distributed uniformly n its circumference The magnetic field 1 increases linearly from the axis of the surface 2 is constant inside the tube 3 is zero only on the axis is zero just out side the tube 3 FREIT uch akit ataci granta 1 2 3 3 4 3

and variable temperature For an ideal gas the fractional change in its volume per degree rise in temperature at constant pressure is equal to T is absolute temperature of gas 1 7 3 7 1 2 T 4 72

4 magnetic equator The magnetic field is now thought to arise due 41 to electrical currents produced by convective motion of metallic fluid consisting mostly of molten iron and nickel in the outer core of the earth This is known as the 1 dynamo effect 2 tidal effect 3 both 1 and 2 4 None of these 3 et 34 1 2 3 1 2 4

n tell on what thing it depends on And explain following q uestion s solution Thank you Have a great day ahead At 20 m from a line source the loudness of the sound is 40 dB At 10 m from the source the loudness will be 43 dB 46 dB 80 dB 37 dB

When a thin transparent plate of thickness t and refractive index u is placed in the path of one of the two interfering waves of light then the path difference changes by 1 u 1 t 3 1 t 2 1 t 1 4 t WO0034 42 In Young s interferring 1 contrast 2 contras 3 numbe 4 numbe

4 2 cm 1 2 m 9 Two walls of thickness d and d thermal conductivities K and K are in contact In the steady state if the temperatures at the outer surfaces are T and T the temperature at the common wall will be 1 3 K T K T d d K d K d T T T T 2 K T d K T d K d K d 4 Kd T K d T K d K d 35 H F 36 S

If magnetic field is perpendicular then force will act on pa rticle then how will the kinetic energy be constant A charged particle enters in a magnetic field in a direction perpendicular to the magnetic field Which of the following graphs show the correct variation of kinetic energy of the particle with time t

27 A 100 W sodium street lamp emits yellow light of wavelength 0 6 m If it converts 40 of electrical energy into light then the number of photons of yellow light it emits per second is 1 1 2 x 1019 2 2 2 x 1019 3 1 2 x 1020 AY 20

A student measured the diameter of a small steel ball using a screw gauge of least count 0 001 cm The main scale reading is 4 mm and that of circular scale is 25 If the screw gauge has zero error of 0 004 cm the correct diameter is 1 0 043 cm 2 0 429 cm 3 0 421 cm 4 0 425 cm

Thermal Properties of Matter 261 22 100 g of ice latent heat 80 cal g at 0 C is mixed with 100 g of water specific heat 1 cal 1 C 1 at 80 C The final temp

etic field vectors present at a point P are given by B B and B respectively as shown in the given figure The magnitude of net magnetic field at point P will be B 5 2 T P 45 1 10 10 2 T 3 20 T B 10 T B 5 2 T 2 10 T 4 10 5 2 T

Find average frequency of collision for oxygen molecule of temperature 300 K and pressure 1 atm Average speed for oxygen molecule is 450 m s and molecular diameter is 2 9 10 10 m A B C D 0 41 x 10 sec 4 1 x 10 0 sec 4 1 x 10 sec 4 1 x 10 sec Correct Answer

If external magnetic intensity on a paramagnetic material is made 4 times and the absolute temperature is made 3 times then how many times will be the self magnetisation 1 4 times 3 times 3 2 4 1 3 3 4 times times 30 fall and an 1 4 T 3 a fond 4 A m 3 THI

ratio of diameters of an air bubble at the bottom and at the surface of a lake is 1 2 What is the depth of the lake 1 atmospheric pressure 10 m depth of water 1 70 m 2 60 m 3 80 m 4 35 m A glass tube 80cm long and open at hath h depth A S

a moving coil galvanometer the coil having N turns and area of cross section A is placed in magnetic field B When current I is passed through it the deflection D on the scale by a pointer attached to the spring of torsion constant k is NA kB I a Y NAB AB k b N KAB NAB I

25 A simple pendulum of period Thas a metal bob which is negatively charged If it is allowed to oscillate above a positively charged metal plate its period will a remains equal to T b less than T c greater than T s d infinite

A solenoid has core of material with relative permeability 400 The winding of the solenoid are insulated from the core and carry a current of 2A It has 1000 turns meter Then magnetising current will be 1 798 A 2 1000 A 3 500 A 4 1494 A 28 uchufelfeen a 400 T 2A his fayd 1 798 A 3 500 A RE for 41

9 If in winter season the surface temperature of lak is 1 C the temperature at the bottom of lake will b 1 1 C 2 0 C 3 4 C

No 24 The magnetic field Band the magnetic intensity H in a material are found to be 0 3 T and 400 A m respectively Calculate the relative permeability p and the susceptibility x of the material

A transformer operates at V 6 kV on the primary side and supplies electric energy at Vs 220 V to a number of houses in a town If the total power consumption of the town is 7 2 kW the current in amperes in the primary is A 2 B 1 2 C 2 5 D 3 E 1

ng y axis an ideal graph is meter of the hole 11 A seconds pendulum clock has a steel wire The clock shows correct time at 25 C How much time does the clock lose or gain in one week when the temperature is increased to 35 C steel 1 2 x 10 5 C 1 321 5 s 2 3 828 s 3 82 35 s 4 36 28 s 12 The apparent coefficient of expansion of a liquid

1 i Two coils A of 12 500 turns and B of 16 000 turns lie in parallel planes so that 60 of flux produced in A links coil B It is found that a current of 5A in A produces a flux of 0 6 mWb while the same current in B produces 0 8 mWb Determine i mutual inductance and ii coupling coefficient

5 Find the net deviation produced in the incident ray for the optical instrument shown in figure Take refractive index of the prism material as 2 1 66 CW 2 66 ACW 3 54 ACW 4 54 CW 30 6

27 4 A B C D Which planets have maximum minimum magnetic fields respectively 1 Jupiter Venus 2 Mercury Mars 3 Jupiter Mars 4 Venus Mercury A solenoid has core of material with relativo 27 3 A C 1 2 3 4 4 A B C D

If current is doubled the deflection is also 14 f doubled in aga 1 Tangent galvanometer 2 Moving coil galvanometer 3 both 1 and 2 4 None of above 1 2 3 1 72 4

Mass M is divided into two parts m and m For a given separation the ratio of for which the m M gravitational attraction between the two parts becomes maximum is 1 1 1 3 1 3 2 1 2 4 1 4

Total amount of work done in establishing the 5 current I in coil of inductance L is 1 W I dl 1 ar 1 41 3 W 2 W LI dl 4 W LI dl L fant 1 3

Convection 3 Conduction 4 Temperature remains same 36 A liquid cools down from 70 C to 60 C in 5 minutes The time taken to cool it from 60 C to 50 C will 1 5 minutes 2 Lesser than 5 minutes 3 Greater than 5 minutes Lesser or greater than 5 minutes depending upon the density of the liquid

Pls explain this with theory 96 The capacitor of capacitance C in the circuit shown is fully charged initially resistance is R After the switch S is closed the time taken to reduce the stored energy in the capacitor to half its initial value is S30 a RC 2 C c 2RCIn2 wwww d R b RCIn2 RCIn2 2 KVPY 2012

evel E M T Quality TA A body of mass 10 kg and velocity 10 m s collides with a stationary body of mass 5 kg After collision both bodies stick to each other The common velocity would be A 3 20 ms 1 B 20 3 ms 1 C 10 3 ms 1 D 3 10 ms 1

An object will continue accelerating until A resultant force on it begins to decrease B its velocity changes direction C the resultant force on it is zero D the resultant force is at right angles to its direction of moti

The volume of a liquid is 26 mL A stud ent measures the volume and finds it to be 26 2 mL 26 1 mL 25 9 mL and 26 5 mL in the first second third and fourth trial respectively Describe measureme nt in the form of precision and accurac y Support your answer

Let A i j and B 1 1 The magnitude of a coplanar vector C such that AC B C AB is given by Online April 16 2018 a c 20 9 b d 10 9 9 12

The pressure P of an ideal gas varies with its absolute temperature T as shown in figure The molar heat capacity of gas during this process is R is gas constant P A 1 7 R C 2 5 R T B 3 25 R D 4 2 R

Example 6 To what potential we must charge an insulated sphere of radius 14 cm so that the surface charge density is equal to 1 Cm2 Solution Here r 14 cm 14 10 m o 1 Cm 106 Cm 2 1 4tr o 4nso 22 9 10 x4 14 10 V 1 9 4nsor T 1 4160 4 ro 2 10 V X

The truth table for the circuit s shown in figure is A B A 0 0 1 1 A 0 0 1 1 BY 01 1 0 0 0 1 0 BY 0 1 1 1 01 1 0 ABY

5 Find out the velocity of Block D m s E 8 m s 2 m s A BI C D m s A VD 22 m s upward direction B VD 22 m s downward direction A VD 23 m s upward direction

Choose the correct option for a semiconductor It has negative temperature coefficient of conductance For pure semiconductor at room temperature ne nh It works as insulator at 0 C All of these

You have two vectors A and B They add up If the size of each vector is maintained the maximum possible size of the resulting vector is achieved if Select one to Vectors point in the same direction b Vectors point in opposite directions c Vectors point in different directions but not opposite

Three blocks of masses 2 kg 3 kg and 5 kg are connected to each other with light strings and are then placed on a smooth frictionless surface 9 The value of Fis 2 kg A 2 N B 3 N 2 1 ms T 3 kg The system is pulled with a force F from the side of the lighter mass so that it moves with an acceleration of 1 ms 2 T and T denote the tensions in the other strings T2 5 kg C 5 N D 10 N

Two blocks each of mass M are resting on a frictionless inclined plane as shown in figure Then A the block A moves down the plane C both the blocks remain at rest 60 30 B the block B moves down the plane D both the blocks move down the plane

3 25 A solid sphere of radius R is gently placed on a rough horizontal ground with an initial angular speed wo and no linear speed the angular velocity and linear velocity v at the end of slipping is 1 wo w R 3 2 5 2 5 Wo 5 Roo 2 4 N 3 NIN N 3 N N 0 3 o Rwo Rwo

When a capacitor initially charged is cor to a inductor the change on the capacit the current in the circuit exhibit the phenom 1 electrical oscillations 2 induction 3 power factor 4 All of these

24 A uniform solid cylinder of radius R is spun and then placed on an incline having coefficient of friction tane 0 is the angle of incline The cylinder continues to spin wihout falling for time 1 2 3 4 Ro 3gsin0 Ro 2gsin0 Ro gsine 2Rw gsing 0 Wo

Two particles P and Q start their motion from same point along same straight line Pmoves with constant velocity 50 m s and starts moving with constant acceleration 10 m s Separation between them after 1 s will be m

4 3 76 S2 A compass is placed between the platesc charging capacitor then its deflection will 1 Be zero always 2 will be non zero always 3 will become zero at steady state 4 None

Consider a point A far away from short dipole p By keeping r constant 0 varies from 0 to 360 Variation of potential of dipole at A with respect to 0 A 1 0 3 0 360 360 0 2 0 4 0 0 360 0 360

The X X bond length is 1 5 and Y Y bond length is 1 48 If electronegativity values of X and Y are 3 and 3 5 respectively then Y X bond length would be 1 1 44 A 3 1 75 A 2 0 98 A 4 0 73 A