Kinematics Questions and Answers

An express train is moving with velocity V meanwhile the driver of this train comes to know that an another train is also moving ahead on the same track with velocity v To avoid collision the driver applies retardation a Then what will be the minimum time to avoid collision V1 V2 B t v2 v2 A t

58 A particle starts moving from rest with constant acceleration Which of the following graphs best shows the variation of its speed v with distance S moved by it 1 3 S 2 4 S

dv de 10 The velocity displacement graph of a particle moving in a straight line is as shown in figure The acceleration of the particle is X 1 Constant 2 Increases linearly with x 3 Increases parabolically with x 4 none of these

3 Abdus salam 4 Ernest Rutherford Figure shows the acceleration time graph of a particle moving in a straight line Which of the following options represents the best corresponding position time a graph t

Two positive point charges of magnitude Qeach are separated by a distance 2a A test charge qo is located in a plane which is normal to the line joining these charges and midway between them The locus of the points in this plane for which the force on the test charge has a maximum value is A a circle of radius r a 2 C a straight line re B a circle of radius r a D an ellipse

Select the correct statements For a particle moving on a straight line 1 Average speed is always equal to magnitude of average velocity f 2 Average speed may be greater than magnitude of average velocity 3 Average velocity instantaneous velocity if velocity is constant 4 Moving with constant acceleration average velocity for a given time interval is arithmetic

In the given figure three point charges are situated at the corners of an equilateral triangle of side 10 cm Calculate the resultant force on the charge at B What is its direction 10 cm C q 100 C 10 cm q 100 C 9 10 cm B 100 C

reference to origin and then as shown V 20 m s A 100m 0 O 206 BV 3 J m s 0 100 3m A they will collide B distance of closest approach is 100 m 40 C their relative speed iss

A stone is dropped freely while another is thrown vertically downwards with initial velocity of 2 m s from the same point simultaneously The time requ by them to have a distance of separation 22m between them is 3 44 sec 1 11 sec 2 5 5 sec 4 22 sec 1

37 A body is projected vertically upward with speed u The velocity v versus position x is best represented by 1 3 B U U 2g 2g X X 2 4 AN U ul 2g U 2g X X

2 gH n 2 u 4 gH n 2 2u 3 2gH n u A man A is sitting in the rear end of a long compartment of a train running at constant horizontal velocity tosses a coin to a person B near the front end of the compartment The trajectory of the coin is as seen by B and a person C on the ground will have 1 different vertical ranges but equal horizontal ranges 2 equal horizontal and equal vertical ranges 3 equal vertical ranges but different horizontal ranges 4 different vertical and different horizontal ranges i ii iii iv F

Two boys A and B initially separated by a straight line distance a on the ground If A and B both start running simultaneously with same speed as shown in figure The distance of their closest approach will be A 60 B 1 3 8 2 3a 2 V a 2 2a 4 a

The displacement time graphs of two moving particles make angles of 30 and 45 with the time axis the ratio of their velocities is AIIMS 2018 1 3 2 2 1 2 Displacement 45 30 Time 3 1 1 4 1 3 RELATIVE M A pers Has de Delhi i that hin

V8 S An object projected upward acquires a velocity of 9 8 m sec when it reaches of the maximum height The maximum height reached is 1160 hve 0170

A cyclist paddling at a speed of 10 m s on a level road takes a sharp circular turn of radius 10 m without reducing the speed The angle made by cyclist with vertical is NCERT Pg 105

A man is running with velocity 5 km h towards east and rain is falling vertically down with speed 5 km h Direction of rain w r t man is NCERT pg 76 AL tical

Particle A is moving with velocity 61 10 m s and particle B is moving with velocity 3 6 m s Magnitude of velocity of A w r t B is

Taking y axis along line of greatest slope of the given inclined plane and x axis perpendicular to it as shown in figure A body is projected along the inclined plane with speed 10 m s at an angle 53 with x axis from origin O g 10 m s 7 Paragraph for Question Nos 7 and 8 Speed of body after t 2 sec is A 2 10 m s 13 m s y 53 B 42 m s D 2 13 m s 10 m s

A graph between square of speed with time t for a particle moving on a straight line The acceleration of the particle at t 1 s is V x 2as xzaxlaf v da d 30 1 1 m s 2 1 5 m s2 3 2 0 m s2 4 2 5 m s2 12 2 32

4 Constant momentum 13 A ball is thrown horizontally from the top of tower 100 m high with speed 10 m s After 2 seconds of fall gravity disappears Then total time taken by ball to reach the ground is g 10 m s 1 10 s 2 8 s 3 6 s 4 4 s O R 2u sin 0 coro g pusin ya os 40

A block of mass m moving with speed u undergoes head on elastic collision with another mass m at rest The fraction of energy transferred by m to m is 1 m m m m 2 2m m 2 3 m m 2 m m m m 2 4m m 4 m m

n time a t graph of a particle moving in a straight line is as shown Particle starts from rest Time t when the velocity again becomes zero is a m s 2 1 3 s 2 2 3 s 3 2 2 s 4 2 6 s t s

The acceleration time a t graph of a particle moving in a straight line is as shown Particle starts from rest Time f when the velocity again becomes zero is S a m s 2 0 1 3 s 3 2 2 s 2 t s 2 2 3 s 4 2 6 s

If a trolley starts from rest with a constant acceleration of 2 m s the velocity of the body after 4s would be i ferien A 2 m s 2 B 8 m s 14 C 4 m s D 6 m s

NUMERICAL BASED DECIMAL TYPE In the system shown in the figure a bead of mass m can slide on the string There is friction between the bead and the string Block B has mass equal to twice that of the bead The system is released from rest with length 18 75 m of the string hanging below the bead Assuming the pulley and string to be massless Find the distance in meter moved by the block B before the bead slips out of the thread On the figure shown two blocks each of mass 2 kg are connected through a massless inextensible string which passes over a frictionless pulley The coefficient of friction between any two surface is B 2 kg bead 18 75 m

A ball of 4 kg mass moving with velocity 40 m s in east direction collides with another ball of 6 kg mass moving with velocity 20 m s in east direction After collision two balls stick together then loss of kinetic energy is NCERT Pg 129 1 360 J 3 480 J 2 240 J 4 600 J nes of

A block of mass m falls vertically on a horizontal floor of coefficient of restitution e 0 8 The fraction of energy lost during collision is 1 0 64 2 0 80 3 0 20 4 0 36

3 A sphere is projected with a velocity u at an angle to the horizontal ground from A It hits a smooth vertical wall at a certain distance R from A and again reaches back to A The co efficient of restitution for the collision is e Let R H and T be the range maximum height reached above A and the time of flight respectively if the wall is not present Also H T are the maximum height of the sphere above A and the time of flight for the path with collision with wall Then 1 H H 2 T T 3 R R 4 A R R R 2e e

A large wooden raft is flowing with a river stream A man on the raft dives into river and swims down the stream for 15 minutes and then he turns about and comes back to the raft The swimming speed of man is 5 km h in still water and the river is flowing with speed 4 km h The distance moved by the raft till the man comes back to raft is 1 1 km 2 2 km 3 3 km 4 4 km

9 q 8 3 2 what value of q P will be maximum 98 If P where is a constant then for

A boat takes two hours to travel 8 km down and 8 km up the river when the water is still will the boat take to make the same trip when the river starts flowing at 4 kmph 1 2 hour 2 2 hour 40 minute 3 3 hour 4 3 hour 40 minute

A person sitting on the top of a tall building is dropping ball at regular intervals of one second Find the positions of the 3rd 4th and 5th ball when the 6th ball is being dropped

50 A point moves in xy plane according to equation x at y at 1 bt where a and b are positive constants and t is time The instant at which velocity vector is at 4 with acceleration vector is given by b 1 6 d a b a b A ab V ai tall do c 1 a 1 b 1

A train initially at rest at station A starts its journey and eventually stops at station B after travelling a dis tance s The first part of its journey is under uniform acceleration u and the later part under uniform retar dation v Show that the time taken for the journey is 2 s 1 1 1

A rod AB is shown in figure End A of the rod is fixed on the ground Block is moving with velocity 3 m s towards right The speed of end B of the rod when rod makes an angle of 60 with the ground is A 3 m s C 5 m s B 2 m s D 2 5 m s A60 B v 3m s

29 Potential energy of a particle along x axis varies as shown in the figure If the particle is released from rest at a point on x axis UA O 1 1 It will move in negative x direction 2 It will move with constant acceleration 3 v x graph for a particle is parabolic 4 All of those

A body is thrown in upward direction The velocity v of body varies with position x as Parabola r 3 X X 4

3 28 32 m s A particle is projected at an angle of elevation sin 1 and it s range on the horizontal plane is 5 3 km The initial velocity of projection is 1 160 m s 2 175 m s 3 180 m s 4 230 m s qx the

A ball is dropped from a building of height 45m Simultaneously another ball is thrown up with a speed 40 m s Find the relative speed of the balls as a function of time till both balls are in air A remains 40 m s B Zero C 40 10t m s D First increases then decreases

13 A balloon with m is descending down with an acceleration a where a g How much mass should be removed from it so that it starts moving up with an acceleration a AIPMT 2014 1 3 2ma g a ma 2 4 2ma g a ma

4 In a soccer practice session the football is kept at the centre of the field 40 yards from the 10 ft high goalposts A goal is attempted by kicking the football at a speed of 64 ft s at an angle of 45 to the horizontal Will the ball reach the goal post

98 A rod of mass m length is moving between perpendicular smooth walls as shown When rod is at angle 8 with horizontal its end A is moving right with speed v The speed of end B is YA 1 v cote 2 coco B 0 X A V 2 v tane 4 y sine

3 The accompanying graph of position x versus time t represents the motion of a p are both positive constants the expression that best describes the acceleration a of the particle is KVPY SA 2013 R a p qt C a p qton D a p qt

A student starts from his house with a speed of 12 kmh and reaches the school 3 min late Next day he increases speed by 1 kmh and reaches the school 3 min earlier Find the distance between his house and office

A car weighing 100kg is on a slope that makes an angle 30 with the horizontal The compo nent of car s weight parallel to the slope is g 10ms 1 500 N 3 15 000 N 2 1000 N 4 20 000 N

1 A 8 3 B 20 6 C 13 A particle is moving along a straight line Its velocity time graph is as shown in the adjacent fig Then Match the following IJSO Stage 1 2014 Physical quantity i Acceleration at 4 second 1 Velocity at 4 second iii Direction of motion at 2 second v ms 4 2 Remarks p Positive q Negative r Zero libris ii 0 vi bns iii A 123456 t s no 8 noltchey ori eworte rosie oft boshue leshori 6 evado teor mont besesion el led A a A Jusqmi vrova in begnad el rigong ell no eine erff elane of ton viibolov 211 2002 02 A i is p ii is q and iii is r is 1301100 616 tel 00 B i is r ii is r and iii is p

The take off speed of Airbus A340 is 288 km hr From the taxi track it comes to the main runway and waits for a while for the final clearance from Air Traffic Control The aircraft then achieves this speed within 50 seconds Neglecting the effect of the wind direction and friction what should be the minimum length of main runway decided by civil engineers for this aircraft for a lake olf A 2400 m IJSO Stage 1 2017 D 1800 m B 2200 m C 2000 m

15 he positions of two blocks at successive 0 20 second time intervals are represented by numbered squares in the figure below The blocks are moving towards right IJSO Stage 1 2017 6 A 17 Block a Block d H S 1 2 piens ast yoneupetl to noilgibet pilongsmorosia to nojart svor plo The accelerations of the blocks are related as follows aXonsig 26 A acceleration of a is greater than acceleration of b om 3 ans B acceleration of a equals acceleration of b Both accelerations are greater than zero ol C acceleration of b is greater than acceleration of a 0286m 071301 D acceleration of a equals acceleration of b Both acceleration are zero con A

A ball is dropped from the roof of a building reach the ground in 5 s If ball is stopped after 3 s of its fall and then allowed to fall again then the time taken by the ball to reach ground for the remaining height is 1 1 s 3 3 s 2 2 s 4 4 s

If a body losses half of its velocity on penetrating 3cm in a wooden block then how much will it penetrate more before coming to rest 1 1 cm 2 2 cm 3 3 cm 4 4 cm