Kinematics Questions and Answers

A ball is projected from to of a tower of height 80m with u 50m s at an angle 37 with horizontal Find range time of flight 50ms 80 m 37 A B C D 320 m 8 sec 400 m 10 sec 300 m 8 sec None

A train travelling at 20 km hr is approaching a platform A bird is sitting on a pole on the platform When the train is at a distance of 2 km from pole brakes are applied which produce a uniform deceleration in it At that instant the bird flies towards the train at 60 km hr and after touching the nearest point on the train flies back to the pole and then flies towards the train and continues repeating itself Calculate how much distance the bird covers before the train stops olution For retardation of train v u 2as 0 20 2 a 2 a 100 km hr 1 Time required to stop the train v u at 0 20 100t t hr For Bird speed Distance 1 S V x t 60 x 12 km

1 A car travels with a speed of 20 kmph for one half the distance and other half at 30 kmph If its acceleration is uniform its average speed is B 25 kmph 1 A 24 kmph C 10 kmph D 12 kmph 2 The motion of a particle is represented by the equation s s 4t 8t 5t 4 Its m s acceleration at the end of 2 second is B 40 A 32 A 0 B UNIT TEST NOV 2021 PHYSICS 6 ms 3 The diagram shows the displacement time graph for a particle moving in a straight lir The average velocity for the interval t 0 t 5 is 2 ms C D 2 ms M C 37 4 From the following displacement time graph velocity of the moving body A ms m s B 3 ms C 3 ms 1 D ms 1 X uestion No 1 10 0 10 Mark Correct Time sec N 2 D 35 30 5 If a body is thrown up with the velocity of 15 m s then maximum height attained by the body is g 10 m s A 11 25 m B 16 2 m 6 A projectile fired with initial velocity u at some angle has a range R If the initial velocity be doubled at the same angle of projection then the range will be A 2R B R 2 C R D 4R Displacement meter C 24 5 m Oh 43m 26s D 7 62 m Answer Sheet Answer Next Marks 4 00

4 Only i and iii Two particle are oscillating along two close parallel straight lines side by side with the same frequency and amplitudes They pass each other moving in opposite directions when their displacement is half of the amplitude The mean positions of the two particles lie on a straight line perpendicular to the paths of the two particles The phase difference is AIPMT MAINS 2011 C

A cylinder is free to rotate about its axis It angularly accelerate from rest at the rate of TT rad s for a period of 3sec and then it is suddenly reversed in dire without changing the magnitude The angle rotated by the cylinder in time interval 6 to 10 sec is 0 radian If n fill n in the OMR sheet

Two blocks A and B of same mass M are connected with each other with an ideal string of length 2 passing over an ideal pulley The block A is connected to a light pan C with an ideal string as shown in M figure A particle of mass 2 is dropped on l pan from height 2 as shown If collision between particle and pan is perfectly inelastic acceleration of B just after the collision is M MM A B l

1 m Two balls A and B of masses 1 kg each are connected by an inextensible massless string The system is resting on a smooth horizontal surface An impulse of 10 Ns is applied to the ball A at an angle 30 with the line joining two balls in horizontal direction as shown in the figure Assuming that the string remains taut after the impulse if the magnitude of kinetic energy of ball A is 175 k Find the value of K 8 1 kg B30 1 kg A 10 N

3 13 the 54 What should be the value of does not slide over the triangular wedge surfaces are smooth m 4 m m 5 1 m 2 4 3 1 m 5 3 1 2 4 5 5 m 30 M

A train is moving towards east and a car is along north both with same speed The observed direction of car to the passenger in the train is A East north direction B West north direction C South east direction D None of the above

PART B Answer all the questions Each question carries 5 marks 1 Find the velocity and the position as functions of the time for a particle of mass m which starts from rest subject to the following force function F x F sinct where F and c are positive constants 12 5 2 51

Two projectiles A and B are projected simultaneously from towers of same height as shown in figure in same vertical plane then 20 m s A 37 50 m 15 m s 53 B Path of A seen by Bis straight line Path of B seen by A is a parabolic A and B collide at t 2 s A and B collide at t 5 s

Two blocks A and B of masses m and 3m are held against a compressed spring on a frictionless horizontal floor with the help of a light thread When the thread is cut the spring forces bo the blocks away and finally the spring drops on the floor and the blocks recede away from each other A MOMOCODE B Which block leaves the spring first O Block A Block B Both the blocks leave the spring

b Two blocks A and B are placed on inclined planes as shown in Fig 3 b The block A weighs 1000 N Determine minimum weight of the block B for maintaining the equilibrium of the system Assume that the blocks are connected by an inextensible string passing over a frictionless pulley Coefficient of friction A between the block A and the plane is 0 25 Assume the same value for B 161 30 Fig 30h 60

8 Two blocks M and M are tied with string and kept at rough surface as shown in figure If F 20 N is applied on the block of mass M then the friction force on the blocks at f 2 s is 1 kg M H 0 6 F 2t 1 6 N 10 N 2 kg M M 0 5 2 6 N ON

28 Two cars A and B are moving on a straight line in the same direction with velocities v and v respectively When they are separated by distance of then car A starts decelerating with value a and car B starts accelerating with a The minimum value of d so that the cars do not collide is 1 3 2 a 8 2 V V 2 a a V V 4 21a 8

33 If velocity v of a particle moving on a straight line as a function of position x is given as v x 5x 4 then acceleration of the particle when velocity of the particle is zero is units are standard 1 Zero 2 2 3 3 4 4 Telegram n

Twelve paintballs are shot at the same speed but different angles at a sloped wall Perhaps it s the side of a pyramid or some other architecturally interesting building They hit the wall at different heights Which has the highest speed when it hits the wall O The paintball that hits highest on the wall O There is not enough information given to answer the question O The paintball in the middle O The paintball that hits lowest on the wall

1 Zero 2 2 3 3 4 4 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 2 5 7 3 9 5 4 9 7 1 Aakash edical IT JEE Foundations Telegram 38 The acceleration time a t graph of a particle moving on a straight line is as shown a m s Space for Rough Work The corresponding velocity time v t graph will be A N H a 4 1 2 NI t s 43 At a metro station a girl walks up a stationary escalator in time t If she just stands on the moving escalator then escalator takes her up in time t The time taken by her to walk up the moving escalator will be 5 24

If a particle is projected from point p on the inclined plane Speed of projection is u inclination angle of plane is 0 45 and the particle is projected perpendicularly to the surface If the distance OP is Then find the angle at which the particle will hit u 2g the horizontal surface i e find the value of 8 0 45

e diagram shows the displacement time graph for a particle moving in a straight line Find the average speed for the interval from t 0 t 3 sec Displacement m N1 N2 1 24 time sec

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

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

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

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

A particle starts moving rectilinearly at time t O such that its velocity v changes with time t according to the equation v t2 t where t is in seconds and v is in m s The time interval for which the particle retards is A t 1 2 1 2 t 1 Marks 4 t 1

Two ships A and B A is at a separation of L north of B are given such that A st arts to move eastward with a constant speed of u and B starts to move with a speed v v u such that it always follow s A Find out after what time B is going to catch A

3 5 m s 4 3 m s A train is moving on a straight line with constant acceleration The front and the rear end of the train passes a standing person with velocities v and v respectively What is the instantaneous velocity of the train when sixty percent of the length of the train has passed that person 1 3 adeduo V2 3 v V 2 2 2v 3v 5

Marks 4 0 A body covers first 1 3 part of its journey with a velocity of 2 m s next 1 3 part with a velocity of 3 m s and rest of the journey with a velocity 6m s The average velocity in m s of the body will be valuo is allowed

Two friends are pulling a train cart down some tracks The first friend is pulling with a force F1 at an angle of 34 degrees from the tracks The second friend is pulling at an angle of 45 degrees with a force of F2 105 N a 10 pts If there is no net force perpendicular to the tracks what is the force F1 b 10 pts The train cart begins to accelerate down the tracks at a 0 32 m s2 What is the mass of the cart GWR Figue

5 The distance between a town and a bus stop is 30 km A man started to walk from the bus stop to the town at 7 30 a m while a cyclist left the town for the bus stop at 7 40 a m riding at a speed of 18 km h The man met the cyclist after walking 6 km determine at what time they met and the man s speed 1 9 a m 6 km h 2 9 a m 4 km h LAY 16

Two blocks of mass 6 kg and 4 kg are connected by a string as shown Acceleration of both blocks when F 100 N is applied on the pulley 6 kg 1 0 0 3 0 15 m s F 4 kg 2 0 2 5 m s 4 6 m s 15 m s

6 A ball is projected upward then it is at same height of 80m at 8s and 10 s What will be its projecti velocity a 1 9 m s e fu fall 2 180 m s 10 3 90 m s 4 45 m s

A high speed car and an innocent insect have a head on collision The force of impact splatters the poor insect over the windshield Is the corresponding force that the insect exerts against the windshield greater less or the same Is the retardation of the car greater than less than or the same as that of the insect

20 If a baseball player can throw a ball at maximum distance d over a ground the maximum vertical height to which he can throw it will be Ball has same initial speed in each case d 2 ovom 3 2d aig 1 2 d Fining 4 d

A defective satellite of mass 950 kg is being towed by a spaceship in empty space The two vessels are connected by a uniform 50 m rope whose mass per unit length is 1 kg m The spaceship is accelerating in a straight line with acceleration 5 m sec2 a What is the force exerted by the spaceship on the rope b Calculate the tension along the rope c Due to exhaustion the crew of the spaceship falls asleep and a short circuit in one of the booster control circuits results in the acceleration changing to a deceleration of 1 m sec Describe in detail the consequences of this mishap

travelling along a track at a constant speed of 40 m s A TV camera man is recording the event from a distance of 30 m directly away from the track as shown in figure In order to keep the car under view in the position shown the angular speed with which the camera should be rotated is Track 30 m TV Camera rad s 3 85 2 rad s 40 m s

6 Two trains 101 m and 99 m in length are running in opposite direction with velocities 54 km h and 36 km h In what time they will completely cross each other 1 20 s 3 10 s 28s 101 4 16 s

201 Two cars A and B start moving from the same poin with same speed v 5 km minute Car A moves towards North and car B is moving towards East Wha is the relative velocity of B with respect to A 1 5 2 km min towards South East 2 5 2 km min towards North West 3 5 2 km min towards South West 4 5 2 km min towards North East

2 Position of a particle moving along x axis is given by x 2 8t 4t the distance travelled by particle from t 0 tot 2 sec is fahit cu fa faf x 2 8t 4t t 0 t 2 34 1 10 2 8 3 12 4 16

A batter hits a 0 3 lb baseball at a speed of v 110 ft s an angle of a 30 so that it strikes an angled wall and rebounds If d 150 ft h 4 ft 0 55 and the coefficient of restitution is 50 find the speed of the ball just after it hits the wall a Just before impact the ball has a speed of ft s along the wall b The ball travels at ft s just after impact round your answers to 3 significant figures ft s normal to the wall and

D A river 2 km wide is flows at the rate of 2km h A boatman who can row a boat at a speed of 4 km h in still water goes a distance of 2 km upstream and then comes back The time taken by him to complete his journey is 1 60 min 2 70 min 3 80 min 4 90 min

flat firing range Part C Part A Determine the maximum height reached by the projectile VAX 89 4 Submit Previous Answers Request Answer X Incorrect Try Again 2 attempts remaining Part B Determine the total time in the air VAE t 8 54 Submit Previous Answers Request Answer X Incorrect Try Again 4 attempts remaining Determine the total horizontal distance covered that is the range m

A helium balloon is released from the atrium floor of Willamette Hall and accelerates upwards at 2 5 m s 2 Air resistance is not a factor How long would it take the balloon to reach the stars on the sculpture 12m above O 2 5s 3 1s O 0 82s O 1 7s

Two objects one sliding down from rest on a smooth frictionless slope the other being thrown from the point O start their motion at the same instant Both get to the point P at the same time and at the same speed Determine the initial angle of the throw enka

An object is projected from ground with speed u angle 0 with horizontal the radius of curvature its trajectory at maximum height from ground is 1 3 u sin 20 g u sin 0 2 u cos 0 2 g u sin 0

8 Let t 3t 4t 3 and 2 t 4t i 3tj represent the positions of particles 1 and 2 respectively as functions of time t t and t are in metres and t is in seconds The relative speed of the two particles at the instant t 1 s will be 1 1 m s 2 3 2 m s 4 7 2 m s men 3 5 2 m s

An aeroplane touches the runway at 270 km h and stops after a run of one kilometre How lomm does it take to stop 26 67 A car accelerates from rest at 2 m s What will be its speed and how far will it be from i starting point after 10 s After what distance will its speed be 40 m s 20 m s 100 m 400 m

Which one of the following statements is not true about the motion of a projectile 1 The time of flight of a projectile is proportional to the speed with which it is projected at a given angle of projection 2 The horizontal range of a projectile is proportional to the square root of the speed with which it is projected 3 For a given speed of projection the angle of projection for maximum range is 45 4 At maximum height the acceleration due to gravity is perpendicular to the velocity of the projectile