Physics Questions

A body is moving with constant velocity on the path shown A B C D m Normal reaction exerted on body by path is greatest at NB Normal reaction exerted on body by path is least at Nc Normal force is greater than weight at B Normal force is lesser than weight at A D

A plane EM wave of frequency 30 MHz travels in free space along the X direction The electric field component of the wave at a particular point of space and time is E 6 V m along Y direction Its magnetic field component B at this point would be O2 x 10 8 T along Z direction O 6 x 10 6 T along X direction O 2x 10 8 T along Y direction O 6x 10 8 T along Z direction

A particle of mass m and velocity v collides oblique elastically with a stationary particle of mass m The angle between the velocity vectors of the two particles after the collision is in degree

2K A body A weighing W descends down on an inclined plane D which makes an angle a with the horizontal and pulls a load B that weighs W by in means of a weightless and inextensible thread passing over a small light pulley C as shown in figure If the horizontal component of the force is 37 W 40 N W 20 N neglect friction g 10 75 newton which the inclined plane D applies on the floor corner E Find the value of K Take a m s B F D

In a plane electromagnetic wave the electric field oscillates sinusoid at a frequency of 2 0 x 1010 Hz and amplitude 48 V m 1 The wavele of the wave in vacuum is 0 1 5 m O 1 5 10 1 m 01 5 10 2 m 01 5 10 m

A boy rides a bicycle back and forth along the ground and the horizontal position of the bicycle is given below Position no 30 30 BO Time seconds a Find the displacement and the distance covered by the bicycle between 0 second and 30 seconds Ans 90km 90km b Calculate the displacement and distance travelled by bicycle between 0 second and 40 seconds Ans 30km 150km c Calculate the displacement and distance travelled by bicycle between 30 seconds and 50 seconds Ans 30km 90km d What is the total displacement and distance travelled by bicycle Ans 60km 180km

A particle of mass 2 kg is moving along a line due to a force F 5x 6 where x is the instantaneous position The particle will perform 1 SHM about x 6 V5 5 2 2 SHM with angular frequency 3 Translational motion with a constant acceleration with a variable acceleration

4 CRANE A simple crane is shown in the below diagram consisted of light rods with length 1 m and 2 m The end of the crane is supporting a 5 kN object Point B is known as a pin It is attached to the main body and can exert both a vertical and horizontal force Point A is known as a roller and can only exert vertical forces Rods can only be in pure compression or pure tension 5 KN C D In kN what is the force experienced by the rod CD Express a positive number if the member is in

34 The block is released after stretching the spring by a distance A from its natural length The graph which represents the velocity of the block will be 1 3 K vooooooooo m smooth X axis NA t 2 t 4 t

Two coils 1 2 are placed as shown in figure Coefficient of mutual induction between 1 2 is M 6 H Find induced emf induced current in coil 2 R of coil 2 is 40 i 4t Coil Coil 2

A block of mass 2 kg is pulled along circular arc from position X to Y as shown in figure The work done by the horizontal force is pulling the block from X to Y is R 30 X 1 FR sin 30 3 FR tan 30 R F F 2 FR cos 30 4 FR cot 30

A bullet of mass 50 g enters a block of thickness t with speed of 500 ms It emerges with 4 of its initial kinetic energy The emergent speed is 1 100 ms 1 2 200 ms 3 300 ms 1

ning f jing m T2 2mg 2 ma 3 ma ig System shown in figure is in equilibrium and at rest The spring and string are massless Now the string s cut The acceleration of mass 2m and m just fter the string is cut will be 1 g 2 upwards g downwards g upwards g 2 downwards g upwards 2g downwards 2 3

9 Two wave are represented by the equatio y a sin ot and a cos wt The first wave 1 Leads the second by 2 Lags the second by 92 3 Leads the second by 4 Lags the second hu T TC 2 wesenspers

A particle of mass M is situated at the centre of a spherical shell of same mass and radius a The gravitational potential at a point situated at 2 distance from the centre will be AIPMT Prelims 2010 A B 3GM a 2GM a

Two coherent sources of different intensities send waves which interfere If the ratio of maximum and minimum intensity in the interference pattern is 25 then find ratio of intensities of sources 1 25 1 2 5 1 3 4 4 25 16

A satellite of earth is to be launched from earth surface in to an orbit of radius 2R Then the additional kinetic energy to be provided to the satellite is mass of satellite is m and mass of earth is M A B 3GMm 4R GMm 4R

The bob of a pendulum is released from a horizontal position If the length of the pendulum is 1 5 m what is the speed with which the bob arrives at the lowermost point given that it dissipated 5 of its initial energy against air resistance

2 21 A ball falls from a height of 1 m on a ground and it loses half its kinetic energy when it hits the ground What would be the total distance covered by the ball after sufficiently long time

22 Consider a gravity free hall in which an experimenter of mass 50 kg is resting on a 5 kg pillow 8 ft above the floor of the hall He pushes the pillow down so that it starts falling at a speed of 8 ft s The pillow makes a perfectly elastic collision with the floor rebounds and reaches the experimenter s head The time olanced i nt th

axes Two events 10 7 s apart in time take place at two points 50 m apart on the X axis Find the speed of an observer moving along the Xaxis who observes the two events simultaneously What will be the spatial separation between these two events as seen by this observer Consider a parallel plate air filled capacitor with a plate area of 10 cm separated by a distance of 2 mm

A bullet fired at an angle of 60 with the vertical hits the ground at a distance of 2 km Calculate the distance at which the bullet will hit the ground when fired at an angle of 45 assuming the speed to be the same Ans 2 31 km

e elapsed in the process is S 23 A battery of EMF 10V sets up a current of 1A when connected across a resistor of 89 If the resistor is shunted by another 89 resistor what would be the current in the circuit in A

A car is moving towards an approaching bike Bike is moving with velocity 30 m s Frequency of horn sounded by car is 100 Hz while it is observed by bike rider as 120 Hz The actual duration of horn is 6 sec Find the time the bike rider hears it in seconds Take velocity of sound in air as 330 m s 5

Consider the following two statements about Oersted s experiments Statement P The magnetic field due to a straight current carrying conductor is in the form of circular loops around it Statement Q The magnetic field due to a current carrying conductor is weak at near points from the conductor compared to the far points Both P and Q are true Both P and Q are false 1 point P is true but Q is false OP is false but Q is true

If a conducting wire carries a direct current through it the magnetic field associated with the current will be Both inside and outside the conductor Neither inside nor outside the conductor Only outside the conductor Only inside the conductor

In the diagram AB is a uniform resistance wire J is a sliding contact which starts sliding at time t 0 from end A towards end B with constant velocity Vo Length of AB is l as shown Power loss in AB at time t will be wwwwwww B A J 0

P PA P2 P Po 1 Tension in the string connecting P P and P is zero 2 Tension in the string connecting P P and P is mg 3 3 Tensions in all the three strings are same and equal to zero 4 Acceleration of P is g downwards and that of P is g upwards

A wire of mass M and length L is placed along x axis with end A at origin The linear mass density of the rod varies as X where x is distance from end A is a constant A A B C B X The value of is 2M Moment of Inertia of the rod about an axis passing through A and parallel to y axis is ML Moment of inertia of the rod about an axis passing through ML COM of the rod and parallel to y axis is 18 Moment of inertia of the rod about an axis passing through B

An object of height 1 cm is placed perpendicularly to the principal axis of a concave mirror of focal length 10 cm at a distance of 10 m from it The height of the image formed by the mirror is 1 0 1 mm 2 1 mm 3 2 mm 4 4 mm

A 30 kg box is pulled across a level floor by a rope that is angled 20 degrees above the horizontal and to the right The coefficient of kinetic friction is 0 1 The tension in the rope is 75 N a Find all the forces acting on the box b Find the work done by each force if the box moves 8 m to the right Show your work

30 Which of the following has dimensions different from remaining three V E H 7 1 Qlou 117 of Inductance Resistance 2 Resistance x capacitance Inductance x capacitance 1 3 4 C H 1 Inductance 1 capacitance Resistance X i rect I 9 H I

An object of mass m is thrown with a velocity vo toward spring as shown in figure in natural length Find value of vo such that it will compress the spring by a distance L Ans Vo k 2 m 4a 2 g 2 X 0 m

A cylindrical parallel beam of light of radius r falls on a thin convex lens of focal length 40 cm and then on a concave lens of focal length 10 cm as shown Area illuminated by beam on the screen is 1 3 f 40 cm f 10 cm 9 r 16 r 30 cm 2 4 50 cm 2 r 4 3 r 16 Screen

In figure all the pulleys and surfaces are frictionless A small block of mass mis pas fixed wedge take g 10ms P3 22 The tension in the string attached to mis 1 40 N 2 10 N 3 20 N 4 5N 23 The acceleration of mis 1 4 5 ms down the incline 2 4 5 ms up the incline 3 5 ms2 down the incline 4 5 ms2 up the incline 24 The acceleration of pulley p is 1 2 25 ms2 towards left 3 9mm t 2 2 25 m tovar

A point charge q is placed at the centre of a cylindrical surface of length 8 CM and radius 3 CM as shown ABCD is a part of curved surface which subtends an angle 0 60 on axis as shown Electric flux through the surface ABCD will be q A 0 D T B C 8cm

8 On a frictionless surface of variable slope a block of mass 2 kg at rest is pushed by applying a horizontal constant force of 40 N as shown The block reaches the top and leaves the surface and falls under gravity alone It strikes the surface some distance away with a speed of 1 10 m s 3 40 m s 40 m 2 20 m s 4 60 m s

An electron is projected with uniform velocity along the axis of a current carrying long solenoid Which of the following is true O The electron will be accelerated along the axis O The electron path will be circular about the axis 1 point The electron will experience a force at 45 to the axis and hence execute a helical path O The electron will continue to move with uniform velocity along the axis of the solenoid

27 A block of mass m 2 kg is moving with velocity v towards a massless unstretched spring of force constant k 10 N m The coefficient of friction between the block 1 and the ground is Find the maximum value of v 5 so that after pressing the spring the block does not return back but stops there permanently 1 6 m s m K 1 mooo 2 12 m s

In sonometer experiment the bridges are separated by a fixed distance The wire which is slightly elastic emits a tone of frequency n when held by tension T If the tension is increased to 4T the tone emitted by the wire will be of frequency MH CET 2015 A n B 2n C slightly greater than 2n D slightly less than 2n

A proton and an electron travelling along parallel paths enter a region of uniform magnetic field acting perpendicular to their paths Which of them will move in a circular path with higher frequency O Electron O Proton Positron Negative proton D 1 po

y A sin kx ot iw mulas Tin b y2 A sin kx wt p and y3 A sin kx wt 20 are superimposed so that y y2 y3 0 at all positions Then the value of is forfavods 2 3 a T b lot c 3 drgnist side ibs d 4 3 TC 2

Biot Savart law indicates that the moving electrons velocity v produce a magnetic field B such that OB is parallel to v Oit obeys inverse cube law it is along the line joining the electron and point of observation B is perpendicular to v

Assume that the mass density of the Sun is uniform and treat solar radiation as blackbody radiation It s given that the surface tem perature of the Sun is 6000 K and assume that the Sun continues giving energy at the same rate in future If the source of Sun s ra diated energy was its gravitational potential energy instead of the nuclear fusion then the Sun will cease to exist in a time of the order of x 10 years 2 10 million years 2 X3 1 billion years 3 X4 1000 years

Two uniform wires of the same material are vibrating under the same tension If the first overtone of the first wire is equal to the second overtone of the second wire and radius of the first wire is twice the radius of the second wire then the ratio of the lengths of the first wire to second wire is MHT CET 2017 A C 133 15 B D 4 1 6

Two objects are connected by a light string passing over a light frictionless pulley as shown The object of mass 6 kg is released from rest g 10 m s A B C D 6 kg 4m m 4kg Time taken by object of mass 6 kg to strike the surface is 2sec Maximum height attained by block of mass 4 kg is 4 8 m Duration after which 6 kg block will leave the surface for the first time is 2 8 sec None of the above

A compass needle is placed above a straight conducting wire If the current passes through the conducting wire from South to North Then the deflection of the compass is O Towards West O O O Towards East Keeps oscillating in East West direction No deflection 1 poi

magnetic field Statement P The magnetic field emerging out of the plane of the paper is denoted by a dot 0 Statement Q The magnetic field going into the plane of the paper is denoted by a cross 8 a Both P and Q are true b P is true but Q is false d Both P and Q are false c P is false but Q is true a O b O c d

31 Work done by force F to move a block of mass 2 kg from A to C very slowly is 76x J Force F is always acting tangential to path Equation of path AB is x 8 y and BC is straight line which is tangent on curve AB at point B u between block and path ABC is 0 5 Then the value of x is g 10 m s 1 2 y 4 0 0 2 3 10 2m 0 5 B 2 m

A 29 0 cm long spring is hung vertically from a ceiling and stretches to 34 7 cm when an 8 50 kg mass is hung from its free end a Find the spring constant in N m b Find the length of the spring in cm if the 8 50 kg weight is replaced with a 215 N weight