Kinematics Questions and Answers

A ball is thrown vertically upwards with a speed of 10 ms 1 from the top of a 200 m high tower and another is thrown downward with same speed simultaneously from the same point Find the time difference between them in reaching the ground in seconds Bond New Delhi 110005 Ph 011 47623456

A block of mass 5kg is moving horizontally at a speed of 1 5 m s A perpendicular force of 5 N acts on it for 4 sec What will be the distance of the block from the point where the force started acting a 2 m b 8 m c 6 m d 10 m

5 A 13 kg block is initially moving to the right with a speed of 15 m s at the instant shown At the instant shown two forces are also acting on the box a constant 110 N force to the right and a constant 45 N force to the left A What is the acceleration of the block B How much time does it take for the box to speed up to 40 m s 15 m s 13 kg 45 N 110 N

3 The displacement x of a particle varies with time t as x ae at be t where a b a and are positive constants The velocity of the particle will a be independent of B b drop to zero when a B c go on decreasing with time d go on increasing with time 2005

A ball is released from the top of a tower of height h metres It takes T sec to reach the ground Bot Instamos a 90x5 TOS 17h D m 18 what is the position of the ball from ground in h A m B 7h m T 13 C second 8h m

A man travelling in car with a maximum constant speed of 20 m s watches the friend start off at a distance 100 m ahead on a motor cycle with constant acceleration a The maximum value of a for which the man in the car can reach his friend is A 2 m s B 1 m s 100 m C 4 m s D None of these

An airplane pilot wants to fly from city A to city B which is 1000 km due north of city A The speed of the plane in still air is 500 km hr The pilot neglects the effect of the wind and directs his plane due north and 2 hours later find himself 300 km due north east of city B The wind velocity is B 106 km hr at 45 N of E D 106 km hr at 45 N of W A 150 km hr at 45 N of E C 150 km he at 45 N of W

Three boys are running on a equitriangular track with the A same speed 5 ms At start they were at the three corners with velocity along indicated directions The velocity of approach of any one of them towards another at t 10 s equals 1 7 5 ms B 2 10 ms 4 0 ms 100 m 60 60 100 m 100 m 60 C

18 v t graph for a particle is as V m s shown The distance travelled in the first 4s is a 12 m b 16 m c 20 m d 24 m 8 t sec

Which of the following quantities remains constant during projectile motion A Average velocity between two points B Average speed between two points C dv dt d dt v D 1 only A 3 A and C 2 only C 4 C and D

Example 3 73 An aircraft flies at 400 km h in still air A wind of 200 2 km h is blowing from the south The pilot wishes to travel from A to a point B north east of A Find the direction he must steer and time of his journey if AB 1000 km

1 A projectile is projected from ground such that 2 second before it reaches the highest point it makes an angle 37 with vertical then the velocity of projectile at highest point is 1 5 m s 2 10 m s A 20 m s

The position time graphs of two cars A and B are straight lines making angles 30 and 60 with the time axis respectively The ratio of velocities of A and B is 1 1 3 3 3 1 2 1 3 4 3 1 on holow The

3 Block A of mass m is to be kept at rest against a smooth vertical wall by applying a force F as shown in figure The force required is 1 mg 2 2mg 3 mg 2 mg A m 30 F

The graph between Ek and is P E kinetic energy and p momentum 1 Ek 3 E 1 p FL 2 Ek 4 EK 1 p

10 An aeroplane moving horizontally from west to eas with some velocity and with an acceleration 5 m s drops a food packet at some instant Then The path of the packet is parabolic with respect to ground b A person sitting on the aeroplane shall see the packet is always vertically below the plane c With respect to plane the packet travels in straight line making an angle tan 1 2 west vertical 1 d With respect to plane the packet travels in straight line making an angle tan 1 2 east vertical e The packet moves in a parabolic path with respec to aeroplane

7 The graph between displacement and time for a particle moving with uniform acceleration is a a Straight line with a positive slope b Parabola c Ellipse d Straight line parallel to time axis

6 The acceleration a of a particle starting from rest varies with time according to relation a at B The velocity of the particle after a time t will be www a b 012 2 B Bt c at d at 2 Bt at B 2

11 A in a moving vertical plane At a certain when instant the link is inclined 60 to the horizontal the point A is moving horizontally at 3 m s while moving in the vertical direction What is velocity of B 1 a 55115 m s 3 m s A VB4 60 b 2 3 m s 3

in the direction During the perio is the componen low and this et along the river bank of a river flowing at a speed as shown in figure What minimum speed relative to water should the man have so that he can reach point B In which direction should he swim V 0 45 A D A Sol Let v be the speed of boatman in still water B 45 B u u b y I c For and Her rive this d t or

41 A skater weighing 70 kg stands on ice He throws a stone weighing 3 kg with a velocity of 8 m s in a horizontal direction Find the distance through which the skater moves back Given 0 02 Ans 0 3 m 12 A block is laid gently on a horizontal conveyor belt moving at a speed of 5 5 m s If the co efficient of friction between the block and the belt is 0 45 find how far the block will move on the belt before coming to rest on Ans 3 43 m it

The variation of velocity of a particle moving along a straight line is as shown in the figure given below The distance travelled by the particle in 5 s is 1 60 m 3 40 m v m s 20 10 0 12 A B bols DE C 3 4 5 t s 2 30 m 4 50 m

8 The displacement of a particle moving along the x axis is given by equation x 2t 21t 60t 6 The possible acceleration of the particle when its velocity is zero is NEE 2016 18m s 2 30 m s 4 9m s F 3 9m s2

2 A 100 m long train crosses a man travelling at 5 kmh opposite direction in 7 2 s then the velocity of train is a 40 ms b 25 ms c 20 ms 1 d 45 ms

If the instantaneous velocity of a particle projected as shown in figure is given by v ai b ct j where a b and c are positive constants the range on the horizontal plane will be y 1 2ab c 3 ac b 2 ab c 4 a 2bc X

c 0 tan Three particles A B and C are thrown from the top of a tower with the same speed A is thrown up B is thrown down and C is horizontally They hit the ground with speeds VA VB and Odisha JEE 2005 DCE 2006 Vc respectively a VA VB Vc b V VB Vc c VB VC VA d VA VB Vc tind to a string of length 1 and is revolved in a

A particle moves along a x axis according to given function x t 10 t 10t Find the average velocity of particle in time interval from t 0 to t t 10 seconds A zero B 5 m s C 5 m s D none of these

The graph shows position as a func tion of time for two trains running on parallel tracks Which statement is true Position A B Time a At time tg both trains have the same velocity tB b Both trains have the same velocity at some time after tB c Both trains have the same velocity at some time be fore tp d Somewhere on the graph both trains have the same

as shown in figure The velocity time will have a shape a a m s and undergoes an acceleration graph from figure L b VI VA

AB is a surface making an angle of 30 with horizontal A is 6 3 m above the ground while B is 3 8 m above the ground A 35 block slides down from A initially starting from rest Its velocity on reaching B is Ar E 9 30 BE 1 7 ms 2 14 ms 3 7 4 ms 4 4 9 ms 36

An automobile travelling with a speed of 60km h can brake to stop within a distance of 20m If the car is going twice as fast i e 120km h the stopping distance will be 1 20m 2 40m 3 60m 4 80m

A body is projected vertically with a speed of 20 m s in a region where g 10 m s The distance travelled in 3 seconds is a 15 m 20 m b 25 m d 30

If block A shown is moving with speed V as observed by a person on ground then the magnitude of velocity of A with respect to the block B is the wedge is fixed 3 A V B 2 C V 3 D Zero 30

A particle is projected upwards with velocity 60 m s In 8 s Average velocity of the particle is A 20 m s B 40 m s Average speed of the particle is B 60 m s A 30 m s 48 49 C 80 m s C 42 m s D 60 m s D 25 m s

A particle moving in a straight line covers first half of the distance into two equal time intervals with speed of 2 m s and 4 m s respectively and second half with the speed of 5 m s The average speed of the particle is 1 4 75 m s 2 4 25 m s 3 4 00 m s 27

The definition of average velocity is a the average acceleration multiplied by the time b distance travelled divided by the time 1 c final velocity initial velocity 2 d displacement divided by the time

116 The position x of a particle varies with time t as 4 X 3 Then the particle is t 1 Slowing down 2 Always moving towards x axis 3 Speeding up LAY Moving with constant speed

3 y 1 5 x 5 A particle starts moving with constant acceleration with initial velocity i 5 m s After 4 second its velocity becomes 31 21 m s The magnitude of its displacement in 4 second is 1 5 m 3 15 mm Or 2 2 10 m B 4 20 m 2 E

An object is at rest Now a force applied to it which give it an acceleration of a 2t ms What will be object velocity at t 3 s 161 61 ms 1 187 6 ms 1 81 61 ms 1 min 91 8 ms 1

2 40 m 3 60 m 4 80 m The relation between time t and distance x is t ax bx where a and b are constants The acceleration is 1 2abv 2 2by 3 2av 4 2ay A car starting from rest accelerates at the rate f through a distance S then continues at constant speed for time t and

A body starts from rest and travels a distance S with uniform acceleration then moves uniformly a distance 2S an finally comes to rest after moving further 5S under uniform retardation The ratio of the average velocity to maximur velocity is 1 2 5 TI 2 3 5 3 4 7 4 5 7 FAIIMS 2018

Two cars leave one after the other and travel with an acceleration of 4 m s2 Two minutes after the departure of the first the distance between the car becomes 28 km The time interval between th departures of the cars is 1 190 sec 2 100 sec

1 91 m 2 182 m 3 293 m 4 111 m A particle located at x 0 at time t 0 starts moving along the positive x direction with a velocity v that varies as v AIEEE 2006 a x The displacement of the particle varies with time as 1 2 1 1 t 2 3 1 4 t it of a particle is y y gt ft If its position is x 0 at t 0 then its displacement after unit time t 1 JAIEEE 2007

city of a rocket with time The time of burning of fuel from the graph is v m s 1000 0 A 10 110 120 B 2 120 e t s 4 Data insufficient JAIIMS 200

A particle is thrown vectically up with an initial velocity 9 m s from the surface of earth take g 10 m s The time in s taken by the particle to reach a height of 4 m from the surface second time in seconds is 1 1 3 2 1 2 3 1 1 4 1 0 AIIMS 2018 Assertion Retardation is directly opposite to the velocity

3 h h h 4 h 2h 3h A particle of unit mass undergoes one dimensional motion such that its velocity varies according to v x 3x 2 where and n are constants and x is the position of the particle The acceleration of the particle as a function of x is given by 1 23 x 2n 1 3 2n x 2n 1 2 2n e 4n 1 14 2n x in 1 NEET 2015

The position x of a particle with respect to time t along x axis is given by x 9t t where x is in metre and t in second What will be the position of this particle when it achieves maximum speed along the x direction AIPMT Scr 2007 3 81 m 2 54 m 1 32 m 4 24 m orticle starting from the origin 0 0 moves in a straight line in the x y plane Its coordinates at a later time are

1 1 m s 27 m s The motion of a particle along a straight line is described by equation x 8 12 t t where x is in metre and t in second The retardation of the particle when its velocity becomes zero is AIPMT Pre 2012 1 24 ms 2 2 zero 3 6 ms 4 12 ms A stone falls freely under gravity It covers distances h h and h in the first 5 seconds the next 5 seconds and the next INEET 2013

07 S 1 S A ball is thrown vertically upwards Which of the following plots represents the distance time graph of the ball during its flight if the air resistance is not ignored AIIMS 2003 11 2 1S 3 s S 1 time graphs shows a realistic situation for a body in motion AIIMS 2004

A charge particle is moving along electric field as shown in figure What is horizontal displacement of the charge particle when it descends a distance of y Given Q m 9 6 x 10 C kg E 5 x 10 V m y 84 cm g 10 m s 0 403 x 108m 2 4 03 x 10 0m 50 g 3 4 03 10 8m 4 8 06 x 10 m AIIMS 2018 14 03X10 3m Lugh that the magnetic axial line is in