Physics Questions

Question 4 Viow In English v In the given figure each plate of capacitance C has partial value of charge Options 1 O CE CER 2 O R r CER 3 R r R wwww R

Find equivalent capacitance between A B Options 1 C 2 O 2 C 3 O 30 4 O 4 C HH X C C 2C 4C Section series

39 A body is allowed to fall from altitude 100 m If the time taken in first 50 m is t and for remaining 50 m is t then neglecting air friction 1 t 3 t 2 4 4 Depends on mass

19 The centre of mass of a non uniform rod of length L whose mass per unit length is proportional to x where x is distance from one end 1 3 3L 4 J N x 0 2 4 x L 514 Space for Rough

The maximum energy stored in the inductors is x J The value of x is cha 892 A B 16 V L 23H 2 Your Answer ellee L 36 H

A potentiometer consists of a wire of length 10 m and resistance 30 Q is connected in series with a battery of e m f 2 5 V and internal resistance 5 Q with external resistance R Q If the fall of potential along the potentiometer wire is 50 HV then value of R in ohm mm is 80 115 100 50

Medical IT JEE Foundation 5 A person is standing at the floor of lift drops a coin The coin reaches the floor of lift in time t if elevator is stationary and in time t if it is moving uniformly then 1 1 1 2 1 1

Options 1 O A 3d View In English v The expression for the equivalent capacitance of the system shown is A is the cross sectional area of one of the plates of side a 3 2 O d 4 30A 0A 6d none of the above 3d

The radius of circle the period of revolution initial position and sense of revolution are indicated in the figure y projection of the radius vector of rotating particle Pis t a y t 3 cos where y in m 2 b y t 3 cos2 t where y in m P 1 0 3 m T 4s

A uniform spring is oriented vertically such that its top end is held fixed If the spring is stretched by pulling its bottom end downward a distance of 4 8cm how far does the spring s center of mass move 4 8 cm 2 4 cm it doesn t move at all not enough information given

A block of mass m 1 2 kg is attached to a string that is wrapped around the circumference of a wheel of radius R 8 2 cm The wheel rotates freely about its axis and the string wraps around its circumference without slipping Initially the wheel rotates with an angular speed w causing the block to rise with a linear speed v 0 27 m s Figure 1 gure y h V 6 0 1 of 1 111 V 0 Part A Find the moment of inertia of the wheel if the block rises to a height of h 6 7 cm before momentarily coming rest Express your answer using two significant figures VAZO I 0 090 Submit Previous Answers Request Answer Provide Feedback X Incorrect Try Again 4 attempts remaining kg m Ne

3 If four forces act at a point O as shown i the figure and if O is in equilibrium then th value of P are 1 150 10 2N 2 45 10 N 1 3 75 10 2 N 20 N 10N 10 N

An electron moves in a circle of radius 1 0 m with a constant speed of 4 0 x 106 m s The current at a point on the circle is approximately O 1 0 10 11 A 1 0 10 2 A 1 0 10 13 A 1 0 x 10 10 A

A uniformly charged rod is kept on y axis with centre at origin as shown Which of the following actions will increase the electric field strength at the position of the dot dot x Charged rod make the rod longer without changing the charge make the rod shorter without changing the charge make the rod shorter without changing the linear charge density

5 The displacement of a particle along the x axis is given by x asin oot The motion of the particle corresponds to a simple harmonic motion of frequency w b simple harmonic motion of frequency 300 2 c non simple harmonic motion d simple harmonic motion of frequency 2 201

A satellite is put in an orbit just above the earth s surface with a velocity 1 5 time the velocity for a circular orbit The maximum distance of the satellite from the surface of the earth is nR where R is radius of earth Find n

4 0 g of a gas occupies 22 4 lites at NTP The specific heat capacity of the gas at constant volume is 5 0 JK mol If the speed of sound in this gas at NTP is 952 ms then the heat capacity at constant pressure is Take gas constant R 8 3 JK mol 1 7 0 JK mol 1 3 8 0 JK mol 2 8 5 JK mol 1 4 7 5 JK 1 mol

2 Motor M exerts a constant force of 300 N on the cable Determine the distance S the crate will travel when its speed is 12m s The crate starts from rest and the co efficient of kinetic friction 0 3 Use Work and Energy method to determine S Also find how much time t will it take to achieve 12 m s speed You can use any method to find t M 20 300 T 300N

3 0 01 mm 4 0 02 mm If force F velocity v and kinetic energy E an taken as fundamental units then dimensional formu for time in them is 1 EFV 3 FvE in a new system of unit the unit of mass is 10 k 2 EF 4 EF 2

2 3 5 A proton moves along horizontal line and towards observer the pattern of concentric circular field lines of magnetic field which produced due to its motion 1 ACW In horizontal plane 3 CW In horizontal plane An electron moves along vertical line and towards observer the pattern of concentric circular field lines of magnetic field which is produced due to its motion 1 ACW In horizontal plane 3 CW In horizontal plane A current is flowing in electricity line towards north the direction of magnetic field at a point which is just below the line 1 1 towards north 2 towards south 3 towards east 4 towards west A current is flowing in a vertical wire in downward direction the direction of magnetic field of a point which is just right side to the wire 1 towards north 2 towards south An equilateral triangle of side a carries a current T Magnetic field at point P which is vertex of triangle Hol 2 3ra 2 2 ACW In vertical plane 4 CW In vertical plane Hol 2 3na 2 ACW In vertical plane 4 CW In vertical plane 3 towards east 4 towards west

A battery of e m f 2 0 V and internal resistance 0 5 is connected across a resistance of 9 52 The number of electrons flowing through the cross section of resistance per second is 1 25 1018 1 25 1017 2 5 1018 O 2 5 x 1017

A particle executes simple harmonic oscillation with an amplitude a The period of oscillation is T The minimum time taken by the particle to travel half of the amplitude from the equilibrium position is a T 8 b T 12 c T 2 d T 4 2007

Four positive point charges of charge q each are placed at the corners of a square of sides a The square lies in the y z plane with its center at the origin Now if a uniformly charged rod of length 1 and charge Q is placed along the x axis form x0 to x0 then find expression of the electric force the four point charges exert on the charged rod

25 Acceleration a of a particle moving in straight line a a function of velocity v is given as a g kv when g and k are constants If the object starts from res then velocity of the object after very long time is 1 alx 4 2g k ala

31 The acceleration position a x curve of a particle moving on a straight line as shown If initial velocity of the particle is 5 3 m s then velocity of the particle at x 10 m is a m s 10 5 10 x m

5 A small object is moving on a special slope consisting of a concave and a convex circular are both of which have a right angle at the centre and radius R 0 5 m and they join smoothly with horizontal common tangent as it is shown in the figure Determine the distance covered by the object on the slope provided that it started from rest and it detaches from the slope at 3 the altitude R The friction is negligibly small LOT

13 A rectangular coil of length 0 12 m and width 0 1 having 50 turns of wire is suspended vertically in a uniform magnetic field of strength 0 2 Weber m The coil carries a current of 2A If the plane of the coil is inclined at an angle of 30 with the direction of the field the torque required to keep the coil in stable equilibrium will be 1 0 24 Nm 3 0 15 Nm 2 0 12 Nm 4 0 20 Nm m

0 8 In an fcc unit cell atoms are numbered as shown below The atoms not touching each other are Atom numbered 3 is face centre of front face 1 3 and 4 3 1 and 2 The nuk 3 2 2 1 and 3 4 2 and 4

This section contains 15 SINGLE CORRECT TYPE questions Out of these 15 questions A current is flowing through the sides of equilateral triangle of side a The magnitude of magnetic field at the centroid of triangle is Ho Bi 3i 2 a Mo gi 2 a Ho 6i 2 a O No 6 3 2 Read More a

A cat dozes on a stationary merry go round at a radius of 5 8 m from the center of the ride The operator turns on the ride and brings it up to its proper turning rate of one complete rotation every 7 7 s What is the least coefficient of static friction between the cat and the merry go round that will allow the cat to stay in place without sliding

1 Standing waves can not be produced 1 In a string clamped at both ends 2 In a string clamped at one end and free at other end 3 When incident wave sets reflected from the wall super impose 4 When two identical waves with a phase difference of are moving in the same direction super impose

4 horizontal direction 4 Shifted diagonally from initial position Father 80 kg and son 30 kg are sitting at one of the ends of a 4 m long boat 40 kg standing still on water They start to shift slowly Father stopped at centre of boat but son stopped at other end Neglecting friction with water how far does the boat move on the water during the process 1 1 87 m 2 1 5 m 3 1 25 m

of focal length f of the sun formed t is formed by a mal to its principal me screen without t and the screen in on the screen igned parallel to e A light ray is nt just inside one pincides with the number of time ing the first one 30 B Select a graph between v and jul for a concave mirror for real images object formed the mirrors is 2 Telegram ne questionpaper 3 4 lul

c Design a noninverting amplifier circuit that is capable of providing a voltage gain of 15 Assume ideal op amp and resistance should not exceed 30 KN d Find the output of the following circuit 2

34 A body A starts from rest with acceleration a After 2 seconds another body B starts from rest with acceleration a If they travel equal distance in 5th second from the start of A then a a equal to 1 5 9 3 9 5 2 5 7 4 9 7

Three long straight and parallel wires carrying current are arranged as shown in figure The force experienced by 10 cm length of wire Qis R Q P 2 cm 20 A 10 A 10 cm 30 A O 1 4 x 10 4 N towards right 1 4 x 10 4 N towards left 2 6 x 10 4 N towards left 2 6 x 10 4 N towards right

15 The mass of two bodies m and m is given m 2 39 g and m 12 1 g Taking in consideration the significant figures here m m given as 1 14 4 g 2 14 5 g

44 A man swims to and fro along the bank of a river with speed v relative to water If velocity of flow is u then average speed of the man in to and fro motion is 1 Zero 3 U V 2 2 uv 4 v u

A particle starts moving with velocity v along straight line A constant acceleration a exists in the opposite direction of motion At the instant when the particle comes to rest the acceleration reverses its direction keeping its magnitude same The distance travelled by the particle till the instant when it attains same velocity is 28 tonyer 2 3v 280

A person crosses a river along the path AB and again returns to A through same path BA River flows with speed up and the person s speed with respect to water is v constant If the path AB makes an angle 0 with the river flow then find the ratio of time to cross the river from A to B and to return to A from B to A v uo B U

There was initially 100mg of radioactive material After 6 hours its mass decreased by 3 If at any instance its disintegration is proportional to the quantity of material present determine how much is left after 24 hours

From a solid sphere of mass M and radius R a spherical portion of radius R 2 is removed as shown in the figure Taking gravitational potential V Oatr the potential at G gravitational constatn

D The position time graph of a body is given X A B t For the motion between B and C a Velocity increases and acceleration ve velocity decreases and acceleration ve c velocity increases and acceleration is b ve d velocity decreases and acceleration is Fig 3 9 ve

is equ acceleration is 7 Mark the correct statements a The magnitude of the velocity of a particle to its speed b The magnitude of average velocity in an interval equal to its average speed in that interval 3 c It is possible to have a situation in which the spee of a particle is always zero but the average speed is n to 1 zero d It is possible to have a situation in which the spee of the particle is never zero but the average speed in a

7 The velocity v of a particle moving on a straight line as a function of time t is given as v v gt ff where vo g and fare constants If the particle starts from origin then its displacement just after t 1 s is stion paper 3 g 2 v g f 4 2a 3f

Two coils have self inductances L 4 mH and L 8 mH Current in both the coils is increasing at same rate At an instant when power given to the two coils is same find ratio of currents in the inductors L and L2

decrease d are true d are true length f produces of the object then mirror is 4 15 cm A square wire of side 3 0 cm is placed 25 cm in front of a concave mirror of focal length 10 cm with its centre on the axis of the mirror and its plane normal to the axis The area enclosed by the image of the wire is 1 7 5cm 3 4 0cm 2 6 0cm 4 3 0cm

Which statement about a moving object is correct A When an object is accelerating the resultant force acting on it must equal zero B When an object is moving at a steady speed the air resistance acting on it must equi zero C When an object is moving at a steady speed the resultant force acting on it must equa zero D When an object is moving there must be a resultant force acting on it

A professor was fishing in Durban during the summer holidays of the year 2020 and happened to hook a bag of treasure that sank in the ocean many years ago He pulled the treasure up through the water at a constant speed with a tension of 140 N Calculate the tension he used to lift the bag when it was in the air The densities of the treasure and seawater are 19300 kg m and 1030 kg m respectively

A body starts from rest with a uniform acceleration of 8 m s Calculate the time in 2 which body attains a velocity of 160 m s How much distance will be travelled by the body in this time 01 Ans 20 s 1600 m