Basic Physics Questions and Answers

3 A projectile of mass m is fired with velocity from a point as shown in figure neglecting air resistance what is the change in momentum when leaving from P and arriving at Q 30 P 1 Zero 01 AV 2 mv AY 2mv Q

A ball of mass 3 kg is moving at speed of 20 ms makes a head on collision with an identical ball at rest The kinetic energy of the ball is 3 4 th of the original The coefficient o restitution is 1 IN 2 13 1 1 1

Sec 6 3 Consider a block with a mass of 1 82 kg that is tied to the end of a rope R 5 34 m long The block moves in a circular ortit on a frictionless horizontal surface see figure If the maximum tension that the rope can withstand without breaking is 48 2 14 the maximum tangential velocity that the mass can have will be approximately R 6 18 m s 11 89 m s O 61 84 m s 1 19 m s

If A 21 3 and B 51 7 then the vecto having the magnitude of A and direction of B would be 1 2 1 74 21 33 2 74 5 7 direction of B 13 Vector 51 71 4 5 13 i 7 13 3 13 1 2

A liquid dose containing radioactive substance x is scheduled to be prepared at 9 AM and 1 ml of it is given to a patient at 10 30 AM If patient gets late and takes the dose at 11 15 AM how much quantity of dose should be given to patient Half life of x is 90 min A 4 ml B 1 41 ml D 2 82 ml C 2 ml

Attempt All 35 questions The length and breadth of a rectangle are 5 5 0 1 cm and 2 5 0 1 cm Calculate area of the rectangle with error limit A B C D 13 0 8 cm 14 0 8 cm 13 0 6 cm 14 0 6 cm Correct Answer

If an inclined plane is made slowly horizontal by reducing its inclination with horizontal the component of weight parallel to the plane of block resting on the inclined plane A remains same B increases C decreases D first increases and then decreases

Note All questions are compulsory Each question carry 1 mark 1 The mathematical expression of density is Density mass volume Density mass x volume a b C d Density area x mass Density volume x weight 2 Density of water in SI system is 3 1000 b 100 c 10 d 1 3 If the density of object is more than water it will Float on water a b Sink in water c d Neither floats nor sinks Both a and b 4 Which physical quantity is measured in dyne centimetre Torque Moment of force a b c Turning effect of force d All of the above 5 If the perpendicular distance between fixed point and poin of application of force increases the moment o force a Increases b Decreases c Remains same d None of these 6 The SI unit of pressure is a Newton metre b Dyne centimetre c Pascal d None of these 7 A force of 10 N acting on a body causes a displacement of 2m in its own direction The work done by the force is a b c 5 joule d 0 joule 10 joule 20 joule 8 If the mass of the body is doubled the kinetic energy will be a Same b Halved c Doubled d Four times 9 Force applied on a wall of the room results in a Negative work done b Zero work done c Both a and b d None of these

1 If x and y be the distances of the object and 31 image formed by a concave mirror from its focus and f be the focal length then 1 xf y 2 xy f 3 x y f 4 x y f

In secondary rainbow there are 1 1 total internal reflection 2 2 total internal reflection 3 No internal reflection 4 Depends on the size of water droplet WOW 13 Edlech s 1 2 a 3 4 3

direction of ray of light incident on a concave mirror is shown by PQ while direction in which the would travel after reflection is shown by four rays marked 1 2 3 and 4 which of the four rays correctly shown the direction of reflected ray P 24 f f r fa st a

14 15 The following graph shows two isotherms for a fixed mass of an ideal gas The ratio of r m s speed of the molecules at temperatures T and T is P 10 Pa 3 2 1 0 2 V m 3 T ALLI 1 2 2 2 2 3 2 4 4 Six moles of an ideal gas perfomrs a cycle shown 15

36 Energy released in nuclear fusion and fission processes is due to A conversion of the mass difference into energy B chemical reaction C kinetic energy of parent nuclei D above

1 Twelve wires of resistance R each are joined to form a cubical frame Calculate the equivalent resistance between i Two diagonally opposite vertices ii Two adjacent vertices

Give the magnitude and direction of the net force acting on a a drop of rain falling down with a constant speed b a cork of mass 10 g floating on water c a kite skilfully held stationary in the sky d a car moving with a constant velocity of 30 km h on a rough road e a high speed electron in space far from all gravitational objects and free of electric and magnetic

light and d olet light are incident at the same angle on the inclined surface of a prism from air me dium and produce angles of refraction r and v respectively which of the following is c orrect A r v B r v C r 1 v D r v

A block of mass m is connected with a spring of spring constant k and placed on a smooth horizontal surface as shown in the figure The block is then moved to compress the spring by 10 2 cm and then released The collision between block and the wall is elastic The time period of oscillation is k mmmmmmmm 3 1 3T 2 3 T H T 10 cm 19

A person can see his inverted image in a concave mirror when he is 1 between focus and center of curvature C 2 beyond C 3 between focus pole 4 at focus

A particle moves along x axis with speed 6 m s for the first half distance of a journey and the second half distance with a speed 3 m s The average speed in the total journey is A 5 m s C 4 m s B 4 5 m s D 2 m s

becomes 4 times hen a tiny circular obstacle is placed in the path of light from distante source What is observed at the centre of the shadow of the obstacle 1 Dark spot 2 Bright spot 3 Dark bright fringe 4 None

24 A capillary tube is dipped in water and it is 20 cm outside water The water rises upto 8 cm If the entire arrangement is put in freely falling elevator the length of water column in the capillary tube will be 1 20 cm 2 4 cm 4 8 cm 3 10 cm

35 Water is filled in a tank upto 3 m height The base of the tank is at height 1 m above the ground What should be the height of a hole made in it so that water can be sprayed upto maximum horizontal distance on ground 1 3 m from ground 2 1 5 m from ground 3 1 5 m from base of tank 4 2 m from ground 3 m 1m 2 42

An under water swimmer cannot see very clearly even in absolutely clear water because of 1 absorption of light in water 2 scattering of light in water 3 reduction of speed of light in water 4 change in the focal length of eye lens

10 The radius of a planet is twice the radius of earth Both have almost equal average mass densities V and V are escape velocities of the planet and the earth respectively then P a V 1 5 VE c VE 3 Vp b V 2 VE d VE 1 5 Vp Karnataka NEFT 2013

17 A uniform rod of mass m and length 1 is kept vertical with the lower end clamped It is slightly pushed to let it fall down under gravity Find its angular speed when the rod is passing through its lowest position Neglect any friction at the clamp What will be the linear speed of the free end at this instant Solution E Figure 10 W12

7 When a glass capillary tube of radius 0 015 cm is dipped in water the water rises to a height of 15 cm within it Assuming contact angle between water and glass to be 0 the surface tension of water is p 1000 kg m g 9 81 ms 1 0 11 Nm 2 0 7 Nm 1

Mechanical Properties of Fluids 199 22 Eight equal drops of water are falling through air with a steady velocity of 10 cm If the drops combine to form a single drop big in size then the terminal velocity of this big drop is

Q No 30 View In English In order that a thin film of oil floating on the surface of water should show colours due to interference the thickness of the oil film should be of the order of 100 10 000 1mm 1 cm 1 2 3 4 Correct Answer 2 Status unattempted Add to Bookmark List 4

A monkey is sitting on a tree limb The limb exerts two perpendicular forces one of 48 N and another of 20 Find the magnittude of the total force exerted by the limb on the monkey

33 A wave in a string has an amplitude of 2 cm wave travels in the positive direction of x axi a speed of 128 m s and it is noted that 5 con waves fit in 4 m length of the string The equ AIPMT Prelims describing the wave is 1 y 0 02 m sin 15 7x 2010t 2 y 0 02 m sin 15 7x 2010t 002 m sin 785x 10050

A fine in its fine rubber rubber band which in unstretched condition forms a circle of radius r is dropped on a soap film formed over a wire frame When the film inside the band is broken it stretches into a circle of radius nr If the band is cut and used as a single strand to suspend a mass m equilibrium elongation is equal to unstretched length Surface tension of soap film is Question Type Single Correct Type 1 2 S S mg n 1 27nr mg n 1 2nr

A heat conducting piston can move freely inside a closed thermally isolated cylinder which contains an ideal gas In equilibrium the piston divides the cylinder in two equal parts the temperature of the gas being To The piston is slowly displaced The adiabatic exponent of the gas is y 2 The temperature of the gas when the volume of one part is n n 2 times than 3 that of the other part is given by T The value of a B is

A series LCR circuit has R 1022 L 0 1 H and C 10 F The circuit is driven by a 100 V rms source with a frequency that can be varied The maximum value of the time averaged power dissipated over a cycle as a function of frequency is A 100 W B 500 W C 700 W D 1000 W

No 26 View In English A man fires a bullet standing between two cliffs First echo is heard after 3 seconds and second echo is heard after 5 seconds If the velocity of sound is 330 m s then the distance between the cliffs is 1 2 3 Correct Answer 2 1650 m 1320 m 990 m 660 m

A air bubble rises from bottom of a lake to surface If its radius increases by 200 and atmospheric pressure is equal to water coloumn of height H then depth of lake is 1 21 H 3 9 H 2 8 H 4 26 H

No 35 1 2 3 View In English A 20 kg block is initially at rest A 75 N force is required to set the block in motion After the motion force of 60 N is applied to keep the block moving with constant speed The coefficient of static friction i is correct Answer 4 atus unattempted Complete Question Content 0 6 0 52 0 44 0 375 Close

20 The average translational energy of molecules in a sample oxygen gas at 300 K are 3 15 x 10 21 J The corresponding value at 600 K are nearly A 6 3 x 10 21 J C 12 45 x 10 21 J B 1 5075 x 10 21 J D 3 15 x 10 21 J

21 In Boolean algebra A B Y implies that A sum of A and B is Y B Y exists when A exists or B exists or both A and B exists C Y exists only when A and B are both exist

A diatomic gas undergoes adiabatic compression and its volume reduces to half of initial volume then its final pressure would be if gas initial pressure P 1 2 4P 2 P 2 3 2P 4 3 07 P ic custem undergoes cyclic process

a circular disc of radius a has been cut out symmetrically from a uniform squar e plate of side 4a Find out the centre of mass of the given plate

The angular width of c ntral maxima in Fraunhoffer diffraction with the light of wavelength 6000 and slit width 12 x 10 5 cm is O 2 rad O 3 rad O 1 rad O 8 rad

In YDSE the distance between slits is 0 28 mm and distance between slits and screen is 1 4 m Distance between central bright fringe and third bright fringe is 0 9 cm The wavelength of the light is O 5000 O 6000 O 7000 14 16 15 PEIGNE O 9000 LE TE ENTERRA 15 A OLE 43 Sos 1644 1 PARLERAI TALOD NE

49 A massless inextensible string in the form of a loop is placed on a horizontal film of soap solution of surface tension T If film is pierced inside the loop and it convert into a circular loop of diameter d then the tension produced in string is 1 Td 2 Td 3 nd T

The equivalent inductance of two inducto 2 4 H when connected in parallel and 10H connected in series What is the valu inductances of the individual inductors 1 8H 2H 2 6H 4H 3 5H 5H 4 7H 3H New

In Davisson Germer experiment the maximum intensity is observed at Scattering angle 50 and 54 volt Scattering angle 54 and 50 volt Scattering angle 50 and 50 volt O None of these

Two dipoles with dipole moment p 5x 10 KC m and p 9x10 KC m are located at points 0 0 2 m and 0 0 3 m respectively If ele field magnitude at origin is V m then find the value of N 4

Water flows in a stream line manner through a capillary tube of radius a The pressure difference being P and the rate of flow is Q If the radius is reduced to and the pressure is increased to 4P then the rate of flow becomes 1 4Q 3 Q 2 1 2 20 NO 15 16

If TA is mean life of a sample A and is the mean life of sample B From the plot shown which of the following is correct dN dt TA TB TA TB TA TB A B t

A spectral line A 5000 in the line coming from distant star is observed as 5010 The receding velocity of the star is O 1 2 x 107 cm s O 6 x 105 m s O 1 2 x 107 km s O 6 km s

28 A spherical ball is dropped in a long column of viscous liquid The speed v of the ball varies as function of time as 3 3 0 0 4 0 0