Kinematics Questions and Answers

X 11 1 1 4 9 2 1 2 4 3 1 3 5 A point initially at rest moves along x axis Its acceleration varies with time as a 6t 5 m s If it starts from origin the distance covered in 2 s is 1 20 m 2 18m 3 16 m 4 25 m RPMT 2007 from the origin 0 0 moves in a straight line in the x y plane Its coordinates at a later time are

1 2 ms 2 4 ms A rocket is fired vertically from the ground with a resultant vertical acceleration of 10 ms 2 The fuel is finished in 1 mi and it continues to move up What is the minimum height reached 1 42 3 km 2 48 4 km 3 36 4 km 4 25 6 km AIIMS 201

cm Assuming it to be uniform the retardation will be 2 10 x 10 m s 4 15 x 10 m s 3 12 x 10 m s 4 14 5 m s A body A starts from rest with an acceleration a After 2 s another body B starts from rest with an acceleration a If AIIMS 2001 they travel equal distances in 5th s after the starts of A the ratio a a will be equal to 1 9 5 2 5 7 3 5 9 4 7 9 dy starting from rest moves along a straight line with a constant acceleration The variation AIIMS 2003 of speed v with

Preeti reached the metro station and found that the escalator was not working She walked up the stationary escalator in time t On other days if she remains stationary on the moving escalator then the escalator takes her up in time t NEET 2017 The time taken by her to walk up on the moving escalator will be t t 1 1 2 t 1 3 t t 4 1 1 2

1 15 m 2 10 m A particle moves along a straight line OX At a time t in seconds the distance x in metres of the particle from O is given by x 40 12t t How long would the particle travel before coming to rest AIPMT Ser 2006 1 24 m 2 40 m 3 56 m 4 16 m Two bodies A of mass 1kg and B of mass 3kg are dropped from heights of 16 m and 25 m respectively The ratic JAIPMT SCE 2006

A particle moving along x axis has acceleration f at time t given by f f 1 7 where f and T are constants The particle at t 0 has zero velocity In the time interval between t 0 and the instant when f 0 the particle s velocity v is AIPMT Scr 2007 1 f T 2 T 3 f T2 4 6 T and moving with an acceleration 4 3 ms2 in the third second

A man throws balls with the same speed vertically upwards one after the other at an interval of 2 seconds What should be the speed of the throw so that more than two balls are in the sky at any time Given g 9 8 m s AIPMT Scr 2003 1 Any speed less than 19 6 m s 3 more than 19 6 m s 2 Only with speed 19 6 m s 4 At least 9 8 m s

1 s 2s 2 s 3s 3 s 4s 4 S A ball is dropped from a high rise platform at t 0 starting from rest After 6 seconds another ball is thrown downwards from the same platform with a speed v The two ball meet at t 8s What is the value of v Take g 10 ms 2 AIPMT 2010 1 75 ms 2 55 ms 3 40ms 4 60ms ouer of 20m height drops a stone Assuming g 10 ms2 the velocity with which it hi LARMT Sar 201

the particle moves with a constant acceleration A ball is thrown vertically upwards with a velocity of 30 m s If the acceleration due to gravity 10 m s what will be the distance travelled by it in the last second of motion 1 5 m 2x10 25 m 4 30 m m diffono One hall is dropped 2 sec after the other but they both st

1 I m s 2 5 m s 3 7 m s A particle after starting from rest experiences constant acceleration for 20 sec If it covers a distances in first 10 sec RPMT 2003 then the distance covered during next 10 sec will be 1 s 4 4s 2 2s 3 3s uch of mass mare dropped from height h and 2h respectively then the ratio of their times to FRRMIT 2003

A man standing on the edge of a cliff throws a stone straight up with initial speed u and then throws anothe stone straight down with same initial speed u from the same position Find the ratio of speeds the stone would have attained when they hit the ground at the base of the cliff 1 2 1 2 1 2 3 1 1 4 3 1 The height of the bridge is

A ball is thrown upwards it takes 4 s 1 30 ms 2 10 ms 1 3 40 ms 4 20 ms If relation between distance and time is s a bt ct and initial velocity and acceleration Ub 2 ct 2 c 2 b 2 c 3 2 c b 4 b 2 c 2 c RPMT 2 A body falls from a height h 200 m The ratio of distance travelled in each 2 s during t 0 to t 6 s of the jo

The initial velocity of a particle is 10 m sec and its retardation is 2 m sec The distance covered in the fifth second of the motion will be 1 Ym 2 19 m 3 50 m 4 75 m An obiect is released from some height Exactly after one second another object is released from the sam

A rocket is projected vertically upwards and its time velocity graph is shown in the figure The maximum height attained by the rocket is dea culoration after 20 sece 1000 2 10 km M sec J 20 sec 120 3 100 km are of this graph 60 60 km 10006 Z 3 6 5

A truck travelling due to North at 20 m s turns East and travels at the same speed The change in its velocity 1 20 2 m s North East 3 2012 m s South East 3 40 2 m s North East 4 20 2 m s North West 40 Jum hour and the ser

5 The acceleration of a particle moving along a straight line is defined by a as 2 The particle starts from rest at s 20m and it is observed that the velocity is 2 828 m s when s 10m Determine a value of a and b velocity when s 5m 20pts

A block of mass 50 kg resting on a horizontal surface is acted upon by a force F which varies as shown in the figure If the coefficient of friction between the block and surface is 0 2 find the time in second when the block will come to rest g 10 m s F in Newton 200 N 1 2 t in sec

3 Velocity displacement curve of a particle moving in a straight line is as shown Line PB is normal to the curve and line PA is normal to the X axis The instantaneous acceleration of the particle at P is 1 4 A 2 m s AV m s 0 4 O B 1 5 m s A 1 0 B 2 0 C 1m s Sm D zero

A bullet is fired horizontally aiming at an object which starts falling at the instant the bullet is fired Show that the bullet will hit the object

For the two blocks shown in the adjacent figure an external force of 18 N is applied on the lower block Find the acceleration of the upper block in m s 0 4 0 2 2 kg 4 kg 18N

Two carts of masses 200 kg and 300 kg on horiz are pushed apart Suppose the coefficient of friction between the carts and the rails are same If the 200 kg cart travels a distance of 36 m and stops then the distance travelled by the cart weighing 300 kg is DPMT 2002 a 32 m c 16 m A B b 24 m d 12 m PE 79

The equation of trajectory of a projectile is given by 40 x where y is vertically upwards If R y 4x 39 is range and 9 is angle of projection from horizontal then value of R tano is x and y are in m 2 15 6 m 4 14 2 m 1 3 9 m 3 11 7 m

A train is moving towards east at a speed of 20 m s A bullet fired westward with a velocity of 180 m s crosses the train in 1 5 s The length of train is 1 300 m 2 240 m 3 200 m 4 270 m

Three charges q q and q are kept at the corners of an equilateral triangle of side d Find the resultant electric force on a charge q placed at the centroid O of the triangle

A particle is dropped from a balloon rising at 20 m s 1 at a time when the balloon is 80 m above the ground If g 10 m s 2 then the particle reaches the ground approximately in 1 5 6 s 2 6 5 s 3 4 5 s 4 4 s

A ball is projected from a point O with some velocity Vo at an angle 30 with the horizontal as shown in the figure Consider a target at point Q The ball will hit the target then velocity vo is equal to 130 1 2 5 m s 3 4 m s Vo 3 m 2 7 5 m s 4 2 10 m s

5 A bullet of mass 10g moving horizontally with a velocity of 400 m s strikes a wooden block of mass 2 kg which is suspended by a light inextensible string of length 5 m As a result the centre of gravity of the block is found to rise a vertical distance of 10 cm The speed of the bullet after it emerges out horizontally from the block will be 1 120 m s 2 160 m s 3 100 m s 4 80 m s Two identical balls A and B having velocities of 2

A swimmer wishes to cross a river 500 m wide flowing at a rate u His speed with respect to water is v For this he makes an angle with the perpendicular the direction of the flow of the river as shown For u 4 km h and v 2 km h and to minimize the drift the swimmer must flow a path in which should be B O 30 OO O 60

17 The variation of the velocity of a particle mov ing along a straight line is illustrated in the graph given below The distance covered by the particle in 4 seconds is ms 1 a 20 c 40 20 10 0 2 m 3 b 35 d 55

22 utbe d It introduces the concept of the internal energy Consider a car moving on a straight road with a speed of 100 m s The distance at which car can be stopped is HK 0 5 d 100 m a 1000 m b 800 m c 400 m mors m is accelerated uniformly from rest to a

250 When a particle is thrown horizontally th displacement of the projectile at any time t is give by 2 2 1 u g 2 3 u g t 1 2 u t S 2 2 4 u g t 2 4 2

An aeroplane is travelling horizontally at a height of 2000 m from the ground The aeroplane when at a point P drops a bomb to hit a stationary target Q on the ground In order that the bomb hits the target what angle e must the line PQ make with the vertical kg 10 m s AIPMT Mains 2007 Solution Lett be the time taken by bomb to hit the target h 2000 11 291 t 20s R ut 100 20 2000m R 2000 h 2000 tan e 1 0 45 Q 100m s R 100ms P 2000 h 2000m

For a man walking with speed 3 2 km h rain appears to fall vertically downward When he starts running with 5 2 km h rain appears to fa on him at an angle of 45 with vertical The spee of rain w r t ground in km h is 1 22 2 2 6 3 26 0 2 5

Two bulbs of volume V and 4V contain gas at pressures of Satm 1 atm and at temperatures of 300K and 400K respectively When these bulbs are joined by narrow tube keeping their temperatures at their initial values The pressure of the system is 1 latm 2 2 atm 3 2 5atm 4 3 atm

om and worm wheel number of teeth on wheel is 80 The diameters of effort and load drum are 200 mm and 100 spectively Determine velocity ratio for chine

Two swimmers start swimming perpendicular to river flow with different constant speeds at the same time After reaching the opposite bank they have to walk back to reach the point exactly opposite to the starting point at the same time Assume constant walking speed for both the swimmers A Swimmer with greater speed in water will have to walk back slowly B Swimmer with smaller speed in water will have to walk back slowly C Both the swimmers will have to walk back with the same speed D It is possible for both swimmer to reach the end point simultaneously

00 53 36 You are proctored by invigilator BHOLE RAJWARDHAN SANJAY XFx Note Click on image to enlarge it 200N 300 N O 129 29 N O 102 49 N O 129 29 N O 102 49 N Previous Y 100 N

SolveLancer Test Their velocities are shown in graph below In the period of 20 sec what is the maximum seperation between them X m s 10 5 SolveLancer Test a 75 m b 50 m c 72 5 m d 52 5 m a 10 b 20 time sec Y VA 10 m s 10 20 time sec

A particle is dropped from the top of a tower and at the same time another particle is thrown horizontally from the same point Their relative velocity with time in air is A Vertical B constant in a different direction from horizontal as well as vertical C Horizontal D Variable

VB 56 A projectile is projected from the ground with spe 20 m s at an angle 30 with vertical The radius curvature of the path of projectile when velo makes 30 with horizontal is g 10 m s 2 15 4 m 1 8 5 m 3 26 2 m 4 32 6 m nanti

4 If the river wa of rest then what was the displacement of swimmer 9 A man is moving with velocity V finds that rain is falling at an angle 45 with ver When man stops then he finds that rain falling vertically What is the speed of with respect to man A V B V 2 C 2V D None

2 A V A river is flowing with speed V The speed of swimmer is 3V with respect to river Find out the speed of the swimmer with respect to earth while it is moving upstream B 2V A V C 3V D None the cwimmer is swimming upstream then his

39 River of width 500 m is flowing at a speed of 10 m s A swimmer can swim at a speed of 10 m s in still water If he starts swimming at an angle of 120 with flow direction then the distance it travels along the river while crossing the river is i elbihaq 9 6 to to bear 1 250 m grit zasl ed 2 500 3 m 289 500 3 3 m avar viool opsteve 4 500 m 14 qat

5 A cyclist and a motorcyclist are moving with speed V and 2V as shown The separation between them initially is L The sped of both the vehicle is constant Find out the time in which the motorcyclist will overtake the cyclist A 2L V C L V B 3L V D None 2V D ondent to the frame of references forences toment is not true in case of relative motion D

232 If t represents the install instantaneous velocity becomes perpendicular the direction of initial velocity during a projectile to represents the time after which the partic attains maximum height then t t is 1 2 2 6 1 g 2u g u an ad lisw mori eonslab A 16W

A 4V B 4 A swimmer starts swimming upstream and he travels L distance with respect to earth in a given time If the swimmer starts moving down the stream with same speed with respect to river then find out the distance covered by the swimmer in the same time as in the upstream The speed of river flow is V and that of the swimmer is 2V with respect to river A L B 2L C 3L D None

213 A vector A which has magnitude 8 0 is added to a vector B which lies on x axis The sum of these two vectors lies on y axis and has a magnitude twice of the magnitude of B The magnitude of vector B 213 is 1 8 enslqntigrovom albine 3 2 2x8 Honce 8 noitalen gni 4 8 5 wav B 218 The for e each o to rit to F is r ilan bo est oppos 1 Be

3 4 m s 12 A man can row a boat with 8 km h in still water He is crossing a river of width 8 km where the speed of water flow is 4 km h What direction should he head the boat to cross the river in shortest time 1 30 with the current 2 60 with the current 3 90 with the current 4 120 with the current

3 HQ 3 Hp riw 33 A body is projected with same speed at different angles covers the same horizontal distance R If T and T are two time of flights then R is equal to 1 gT T 1 2 2 or 97 A 2 2 gT T alm Evor 8 10 OWT 8S 2 mei numril es 3 T T o isto 4 2gTT26902

72 Two projectiles are thrown horizontally from a high cliff in opposite direction with same speed 20 m s simultaneously At what time velocities of both particles become perpendicular 1 2 2 s 2 2 s 3 4 s 4 4 2s E