Basic Physics Questions and Answers

A large family uses 8 kW of power Direct solar energy is incident on the horizontal surface at an average rate of 200 W per square metre If 20 of this energy can be converted to useful electrical energy how large an area is needed to supply 8kW

2 9680 N 1 8600 N 3 11000 N 4 1200 N 10 Maximum value of static friction is known 1 Limiting friction 2 Kinetic friction 11 3 Normal reaction 4 Coefficient of friction A car having mass m is moving on a ro

1 Two dielectric slabs of dielectric constants K and K2 are filled in between the two plates each of area A of a parallel plate capacitor as shown in the figure Find the net capacitance of the capacitor K K

Assertion A A point charge is lying at the center of a cube of each side L The electric flux emanating from each surface of the cube is 1 6 th of total flux Reason R According to Gauss theorem total electric flux through a closed surface enclosing a charge is equal to 1 0 times the magnitude of the charge enclosed O O Both A and R are true and R is the correct explanation of A Both A and R are true but R is NOT the correct explanation of A O A is false and R is also false OA is true but R is false

How does current density in a conductor vary with a increase in length b increase in temperature assume other factors are constant Justify your answer

Two bullets are resealed from the same height at the same time One is launched horizontally and one is allowed to drop Which bullet will have the greatest rate of acceleration after being released Assume no air resistance Acceleration is the same for both Launched bullet

HAVE CONTROL HAVE PATIENCE BEWARE OF NE 1 Let consider in next birth you become a bird and you are in a air tight cage which is placed over a weighing machine Now what will you do so reading of weighing machine increases 1 nothing 2 fly downwards with acceleration 3 fly upwards with constant velocity 4 fly upwards with acceleration

Select the escape velocity of a particle placed at centre of the earth g is the acceleration due to gravity at surface 2gR 3 5gR 2 2 3gR 4 aulu 3 2 gR allita

Electrons with energy 80 keV are incident on tungsten target of X ray tube K shell electrons of tungsten have 72 5 keV energy X rays emitted by the tube contain 1 A continuous X ray spectrum with minimum wavelength 0 155 A 2 Only a continuous X ray spectrum with all wavelength 3 Characteristic X ray spectrum of tungsten CH 4 Both 1 3

ro from A body starts from rest from a point distance the centre of earth It reaches the surface of the earth whose radius is R The velocity acquired by the body is 1 2GM 3 GM 11 Rro 1 1 2 2 2GM 4 1 1 Ro GM 1 1

A bus is moving on a highway with a speed of v 20 m s A man is at a perpendicular distance of a 60 m from the highway and b 400 m from the bus In order to catch the bus suppose he runs at an angle a from the line of joining him to the bus in initial condition The man can run at a speed of v 6 m s Then the possible values of a so that he can reach any point on the highway at the same time as the bus or before it A 37 B 165 b 7V C 120 D 15

10 A gate having two inputs A B and one output Y is implemented using a 4 to 1 multiplexer as shown in Fig A MSB and Ao are the control bits and I I are the inputs to the multiplexer The gate is NAND AB A To I 1 13 4 to 1 Multiplexer A Ao 0 Y

A microwave oven needs 240 V of electricity to operate and draws 5 A current How much does it cost per month 30 days if it operates 30 minutes per day and TNB charges RM 0 95 cents per kWh CO2 3 Marks

Equal current I flows in two segment of circular loop as shown in figure Radius of the loop is a Magnetic field at the centre of the loop due to segment ACB is C A 7 8 Hod 2a 2 0 Hoi 2 2a B

Consider a binary star system of star A and star B with masses mA and ma revolving in a circular orbit of radii r and TB respectively If TA and TB are the time period of star A and star B respectively then T 02 12 1 T 2 T TB

A particle is acted upon by the forces F a 21 8k F 51 cj bk F3 bi 5 7 Find the value of constants a b c in order that the particle will be in equilibrium A a 6 b 1 c 3 B a 3 b 7 c 4 C a 4 b 3 c 7 D a 0 b 4 c 6

a 5 units due South West b 5 units due 53 North of East 10 units due 37 South of East Then which of the following are correct A a b 21 j C b 0b 0 B a b35 2 D b 51 10j b si

f A monoatomic gas at a pressure P having a volume V expands isothermally to a volume 2 V and then adiabatically to a volume 16 V 5 The final pressure of the gas is take y A 64 P P 64 XC B D 32 P 16 P 2014

A scientist says that the efficiency of his heat engine which operates at source temperature 127 C and sink temperature 27 C is 26 Which of the following gives true explanation 2001 A such an efficiency is impossible B such an efficiency is possible but less probable such an efficiency is quite probable C D data incomplete

Which of the following three physical quantities can be taken as fundamental physical quantities A force mass and velocity B energy force and mass C energy mass and velocity D length acceleration and frequency FA Bl If rocultont of two yootor Din ndiou 6 thon

An ideal gas heat engine operates in Camot cycle between 227 C and 127 C It absorbs 6 x 10 cal of heat at higher temperature Amount of heat converted to work is 2005 A 4 8 x 10 cal B 6 x 10 cal C 2 4 x 10 cal DY 1 2 x 10 cal

In a new system of unit speed of light C gravitational constant G and plank s constant h are taken as fundamental units The dimension of time in this system is given as G hBCY value of a B y is find x X X 22 If in a new system unit of length is 2m unit of time is 3s then x is the numerical value by which given as

D A body is projected with a speed u m s at an angle with the horizontal The kinetic energy at the highest point is th of the initial kinetic energy The value of is 1 30 2 45 3 60 4 120

In the given diagram the reading of the ammeter is when internal resistance of the battery is zero 352 wwww 5 3 213 A 2 A 3 A 60 A www 10 V

3 1 unified atomic mas A 14 B C including the mass of electrons R of the mass of an atom of carbon 14 isotope 1 of the mass of an atom of carbon 12 isotope 12 including the mass of electrons 1 of the mass of an atom of carbon 13 isotope 13 including the mass of electrons D 17 12 2 of the mass of an atom of carbon 12 isotope excluding the mass of electrons

End A and B are connected to the positive and negative terminal of a cell of emf 20 V respectively The value of voltage shown by voltmeter of negligible resistance as shown in the figure is 42 40 A wwwww wwww 10 V 5 V 20 V 15 V V 492 wwww 422 wwwwwww B

A hemisphere rests in equilibrium on a rough ground and against an equally rough wall if the equilibri is limiting then the inclination of the base to the horizontal is Answer A B C Your Attempt 0 sin 0 sin 0 COS 1 1 Correct answer 1 1 1 Rate this ques

48 A thin rod AB of length has linear mass density bx a T where x is measured from A If COM of the rod lies at a distance 10 a bis 1 3 1 3 1 1 1 71 12 2 1 2 4 3 2 from A the ratio

A lead block is suspended from your hand by a string The reaction to the force of gravity on the block is force exerted by 1 The block on the string 2 The string on the hand 3 The block on earth 4 The hand on the string Gels 42 4100 Mariell sy 1 Gas Ga 2 la 3 Geils all 4 GRE Megram Oncestionpaper

4 The boy cannot catch the bus 15 A person walking at the rate of 3km hr the rain appears to fall vertically when he increase his speed 6 km hr it appears to meet him at angle of 45 with vertical The speed of the rain is 1 3 2 km hr 3 6 2 km hr 3 2 km hr 4 2 3 km hr 15 4 193km hr os 6 km hr sua K T 4234 GH 2 1 3 2 km hr 3 6 2 km hr

The values of a number of quantities are used in a mathematical formula and are having same power The quantity that should be most precise anc accurate in measurement is the one 1 Having smallest magnitude 2 Having largest magnitude 3 Used in the numerator motor

MAGNETIC FLUX 3 The magnetic flux linked with a coil of N turns of area of cross section A held with its plane parallel to the field B is NAB a c 2 NAB b NAB d zero

CAREER INSTITUTE PS2OTA RAJASTHANK 9 A 0 5 kg ball moving with a speed of 12 m s 9 strikes a hard wall at an angle of 30 with the wall It is reflected with the same speed and at the same angle If the ball is in contact with the wall for 0 25 seconds the average force acting on the wall is 1 48 N 3 12 N 2 24 N 4 96 N Nurtu s 0 5 kg of AS A RE 244 0 25 ss l eiri 1 48 N 3 12 N 10 Hi

8 A train of 150 m length is going toward north 18 150 m direction at a speed of 10 ms A parrot flies at a speed of 5 ms towards south direction parallel to the railway track The time taken by the parrot to cross the train is equal to sul la 31431 3241 2440 1 12 s 1 12 s 2 8 s 3 15 s 4 10 s 10 3

27 The specific resistance of a material of wire is p and its volume is 3 m and resistance is 3 Q The length of the wire will be 1 12 2 3 45 2 4 5 0 5 0 27 a 34T 51 1 3

ALLEN futai 35 The velocity of a projectile at the initial point A is 21 3 m s Its velocity in m s at poinm B is 1 2i 3 3 21 3 Y 2 21 31 4 21 31

A hypothetical pulse is travelling along positive x direction on a taut string The speed of pulse is 10 cm s and shape of pulse at t 0 is given as y 1 for 6 x 0 x 1 0 If x and y are in cm then for 0 x 1 for all other value of x Vertical displacement of the particle at x 1 cm at t 0 2 s is 5 cm Vertical displacement of the particle at x 1 cm at t 0 2 s is X 4 cm Transverse velocity of the particle at x 1 cm at t 0 2 s is cm s 5 3 Transverse velocity of the particle at x 1 cm at t 0 2 s is

A particle of mass 2 mg is having a charge of 2 C Through what potential difference must it be accelerated starting from rest to acquire a speed of 10 m s Question Type Single Correct Type 1 2 3 5 V 50 V 5 kV

Two concentric conducting spheres are of radii r and r2 The outer sphere is given a charge q The charge q on the inner sphere will be inner sphere is grounded Question Type Single Correct Type 1 2 3 q q 1 4 20

Q No 2 In instrumentation a correction is Knowledge Sections A An error B The revision applied to the indicated value so that the final result obtained improves the worth of the result C Reading error D Range of error degree of correctness 10

2 A ball is thrown at different angles with the same speed u and from the same point and it has the same range in both the cases If y and y are the heights attained in the two cases then y y is equal to 1 2u g 2g 4g 2 Git y y 1 3 13 Hi

Q No 18 The term Allowance in limits and fits is usually referred to A Minimum clearance between shaft and hole B Maximum clearance between shaft and hole C Difference of tolerances of hole and shaft D Difference between maximum size and minimum size of the hole

4 None of these 41 The position of a particle moving on x axis is given by x At Bt Ct D The numerical value of A B C D are 1 4 2 and 5 respectively and S I units are used Find velocity of the particle at t 4 sec 1 48 2 50 3 76 4 78

1 samples X and Y contain equal amount of radioactive substances If Two and Y is 1 2 3 4 2 1 1 2 1 4 1 16 th of the sample X and 16 1 of the sample Y remain after 8 hours then the ratio of half periods of 256

4 2 42 A particle moves a distance x in time t according to equation x t 5 The acceleration of particle is proportional to 1 velocity 3 2 2 distance 3 distace 2 4 velocity 2 3 3 43 Consider the velocity time graph given below It represents the motion of

Two light sources are said to be coherent when their 1 amplitudes are equal and have a constant phase difference 2 wavelengths are equal 3 intensities are equal 4 frequencies are equal and have a constant phase difference

mass M is suspended by a massless string of length L The horizontal velocity v at position A is just sufficient to make it reach point B The angle at which the speed of the bob is half of that at A satisfies A 0 B B MA O 0 3 1 C 2

An object of mass m 8kg rests on an inclined plane that makes angle 0 45 with the horizontal floor What minimum force in N parallel to the base of the incline must be applied to the object in order to begin to move it along the plane parallel to the floor as shown The coefficient of static friction between the object and the plane is s 1 25 O

C i j k D j k For what value of a A 21 aj k will be perpendicular to B 41 21 2k A 4 B zero C 3 D 1 31 C i j k D j k a 11 88 341 412 2i aj k B 41 21 2k ci s A 4 B C 3 D 1

a 2 b 1 c 4 d 6 Mole fraction of glycerine C3H5 OH 3 in solution containing 36 g of water and 46 g of glycerine is a 0 46 c 0 20 b 0 40 d 0 36 1