Kinematics Questions and Answers

A uniform disc of radius 20 cm is performing pure rolling on a moving surface if its angular velocity is 5 rad s then find velocity of its centre of mass A B C D 1 m s 2 m s 3 m s None of these V 2 m s

A cannon fires successively two shells with speed 10 m s the first at an angle 60 and th second at an angle 45 to the horizontal in same plane Find horizontal distance where firing leads to collision of shells take g 10 m s and 3 1 7 Options 1 3 m 2 5 m 3 7 m 19 m

0 7 Single Correct A A Marks 4 00 1 00 hat is nature of acceleration between t 3 s to t 20 s in below diagram x m 2 4 6 8 10 12 14 16 18 20 22 t sec

The Figure shows velocity time graph of two riders Cand D Based on the information represented by the graph answer the following 31 During the first 8 s v m s 5 0 5 0 C D 8 10 t s 1 C has decreasing speed and D has increasing speed 2 C and D both have decreasing speed 3 C and D have the same velocity Chas tho 0

Figure gives the speed time graph of the motion of a car What is the ratio of the distance travelled by the car during the last two seconds to the total distance travelled in seven seconds A 1 9 B 2 9 C 1 3 D 4 9 Speed m s 25 20 15 10 1 2 3 4 5 6 7 Time s

6 rown from a point in a horizontal plane such that its horizontal and vertical velocity components are 9 8 m s and 4 9 m s respectively Its horizontal range is 1 4 9 m 2 9 8 m 3 19 6 m 4 39 2m proiectile IS

A man standing on the roof of a house of heighth throws one particle vertically downwards and another particle horizontally with the same velocity u The ratio of their velocities when they reach the earth s surface will be O 2gh u u O 1 2 O 1 2 O 2gh u 2gh

A bridge is in the form of a semi circle of radius 40m The greatest speed with which a motor cycle can cross the bridge without leaving the ground at the highest point is g 10ms 2 frictional force is negligibly small O 40 ms 20ms O 30ms

A ship is travelling at a speed of 20 knots A knot is a nautical mile per hour a nautical mile being approximately 1 1516 statute miles of 5280 feet each When directly opposite a target it fires a gun whose projectile has a velocity of 2000 feet a second At what angle with the direction of motion of the ship must the gun be pointed in order to hit the target

68 If air resistance is not considered in projecti motion the horizontal motion takes place with 1 constant velocity 2 constant acceleration 3 constant retardation 4 variable velocitu

A body starts from rest with an acceleration 2 m s2 till it attains the maximum velocity then retards to rest with 3 m s If total time taken is 10 seconds then maximum speed attained is A 12 m s C 6 m s B 8 m s D 4 m s

The velocity of a bullet is reduced by 200 m s while travelling through a wooden block in 10 sec The retardation assuming it to be uniform will be A 10 m s C 20 m s B 12 m s D 15 m s

Two balls are thrown horizontally building with speed u and u respectively in opposite directions The separation between two balls when they are moving perpendicular to each other is Acceleration due to gravity is g 1 2 3 2u 42 x U U g 2U1U2 V g 44 g x U U x U U 34 4

A person standing on a moving trolley throws a particle vertically up with speed 3 m s relative to himself as shown in figure Radius of curvature of path followed by the particle as seen from ground at the time of projection is g 10 m s 3 m s 06m 4 m 12 3 g 4 m s

A block of mass m is placed on triangular block as shown in the figure The triangular block is moving horizontally with uniform speed 2 3 m s The acceleration of block of mass m with respect to the triangular block is 5 m s m2 3 m s 30 2 8 m s 3 4 m s 4 6 m s

Q30 63 From NCER In an electromagnetic wave the amplitude of electric field is 1 V m The frequency of wave is 5 x 10 4 Hz The wave is propagating along Z axis The average energy density of electric field in joule m will be 1 2 2 10 12 2 4 4x10 12 3 6 6x10 12 4 8 8x10 12

Between two stations a train accelerates from uniformly at first then moves with constant vel and finally retards uniformly to come to re the ratio of the time taken is 1 8 1 and maximum speed attained be 60 km h then is the average speed over the whole journe 1 48 kmh 1 2 52 km h 1 3 54 km h 1 4 56 km h 1

4 A 300 m long train is moving with a uniform velocity of 90 km h The time taken by the train to cross another train of length 700 m moving with same NCERT Pg 51 speed in opposite direction is 1 56 s 2 68 s 3 20 s 4 92 s

19 If the velocity of a particle is given by v 16x 1 2 m s then its acceleration will be 1 Zero 2 8m s 3 8 m s v 180 16x 2 v dv do 180 16x 4 4 m s 20 A particle is starts moving along straight line ctant acceleration 2m s The ve

1500 N DOM 7777777 TTTTTTT O 3 2000 N Q3 As shown in figure find that at what distance body A will attain a velocity of 3 m s when starts from rest Assume coefficient of friction as 0 2 for block and surface and pulleys are frictionless and weightless

59 A ball is projected upwards from the top of a tower with a velocity of 50 m s making an angle of 30 with the horizontal The height of the tower is 70m After how much time from the instant of throwing will the ball reach the ground 1 2 s 2 5 s 3 7 s 4 9 s

A car that was involved a mishap left a skid marks 120 ft long A witness told that the car was travelling at about 50 miles per hour Was the witness right Justify your answer by showing a solution

A particle is moving along a curve y x x 400 if Vx 2 m s and it remains X constant i Calculate magnitude of velocity of particle when x 20m 05 Marks ii Calculate magnitude of acceleration of particle when x 20m 05 Marks

A golf ball is launched into the air with an upward velocity of 57 feet per second The height of the golf ball after t seconds can be represented by f t using the following function f t 16t2 57t 6 Round all values to three decimal places A Find f 0 B Find f 3 feet feet C Find the time it takes for the golf ball to reach it s maximum height seconds D What is the maximum height feet E When will the golf ball hit the ground seconds F When will the golf ball be 20 feet above the ground Write your answers as a list with your

A barometer kept in an elevator reads 76 cm when is at rest If the elevator goes up with som acceleration the reading wil be 1 76 cm 3 76 cm CO 76 cm nd 4 Zero

1 3 154 Two projectile projected with same speed at angle e and 90 0 from same point then H H equal to where symbols have their usua meanings E 16 3 R Massless string 4 R 155 What is velocity of block when angle between string and horizontal is 30 as shown in the diagram f Block 9 30 202 g2 2 V Smooth surface Aakash Educational Services Limited Regd Office Aaku

53 A ball projected from ground at an angle of 45 just clears a wall in front If point of projection is 4 m from the foot of wall and ball strikes the ground at a distance of 6 m on the other side of the wall the height of the wall is JEE Main Online 2013 a 4 4 m b 2 4 m c 3 6 m d 1 6 m

The maximum range of a bullet fired from a toy pisto mounted on a car at rest is Ro 40 m What will be th acute angle of inclination of the pistol for maximum range when the car is moving in the direction of firing with uniform velocity v 20ms 1 on a horizontal surface take g 10ms 2 JEE Main Online 201 a 30 b 60 d 45 c 75

Problem 1 24 Ball A is thrown upward with a speed of 35 m s from ground while at the same time another ball B is dropped from a height of 100 m with a speed 10 m s 1 along the same straight line By choosing positive direction of X axis and origins for position and time find the height from ground where the two balls meet Take g 10 m s

Ariver is flowing at the rate of 6 km hr A man swims across it with a velocity of 9 km hr Find the resultant velocity of a man

Find 0 23 Obtain formula for magnitude of resultant vector using law of parallelogram Ariver is flowing at the rate of 6 km hr A man swims across it with a velocity of 9 km hr Find the resultant velocity of a man

A body of mass 10 kg moving with speed 2 ms collides with a body of mass 15 10 kg inelastically and sticks to it Then loss in KE of the system will be a 1 875 kJ c 10 kJ b 15 kJ d 5 kJ

A particle which is at rest under the influence of gravity falls that in the last second of its journey it travels at a speed of 53 9 m determines the distance The total time taken to fall is g 9 8 ms 2 5s 4 7s 1 4s 3 6s

8 Acceleration time for a part a 1 Diagram shown in the figure The position time x 1 diagram of the particle corresponding to it is can be represented by 1 a 3 2 E

A particle is projected from ground at some angle with horizontal If P is the point at maximum height H Then the height above the point p where the particle should be aimed to have range equal to maximum height is

Given A ball with a mass of 1 Kg is released from rest at point A and rolls down a quarter circle reaching point B The ball leaves point B with a horizontal velocity Vb and undergoes projectile motion At point C the player headbutts the ball with a force of 1 000 N above the horizontal and the point of impact lasts t 0 005 sec Ignoring air resistance the work done by friction from points A to B is 20 J Find After the player hits the ball at point C what is the ball s highest point and how long does it take the ball to reach the horizontal x axis How much distance was covered Sm 10 Sm VB 6 The impulse changes Tinear momentum MVCE Van VBIX Veln VB x 1 8m v vo

A stone is projected from the point on the ground in such a direction so on to hit a bird on the top of a telegraph post of height h and then attain maximum height 2h above the ground If at the instant of projection bird were to fly away horizontally with uniform speed v 2 2 1 m s Find the horizontal velocity of the stone if the stone still hits the bird while descending

1 0 Avg sol acceleration 22 Sade Clarg 2 freem O see to 2 ser 2 0 2 2 4 db 2 2 2 2 24 2 2 8 m s cans velocity as a function of time Given at t 0 viam s

A particle is constrained to move upward to the right along the path 2y2 x3 3 where x and y are in inches The x coordinate of the particle at any time is x t t 4 Determine component of the velocity at x 6 8 inches Use up to 4 decimal places

A block of mass M is pulled along a horizontal friction less surface by a rope of mass m If a force P is applied at the force end of the rope the force exerted by the rope on the block is O O Pm M m Pm M m OP PM

6 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 a x The displacement of the particle varies with time as a t b t c 1 2 d t

45 The velocity of a particle is v Vo gt ft If its position is x 0 at t 0 then its displacement after unit time t 1 is a v 2g 3f c vo g f 2 46 A particle located at x 0 at time t 0 starts moving b vo d vo g 2 g f 1 3 f

A ball is projected from ground with speed 10 3 m s at angle 60 from the horizontal After how much time in s its velocity makes angle 60 with the vertical Take g 10 m s Figure shows

A force F applied to a body A of mass m produces an acceleration of 4 m s If the same force F is applied to another body B of mass m then an acceleration of 10 m s is produced in the body A and B are then tied together and the same force is applied to the combined body What is the acceleration of the system 01 m s 2 0 20 27 m s m s 7 0 m s 20

A body of mass m moving with velocity v collides elastically head on with another body of mass 2m which is initially at rest The ratio of kinetic energy of colliding body before and after collision is 1 3 1 2 4 1 3 9 8 4 91

A projectile is fired from a cannon located on a horizontal plane If we think of the cannon as being located at the origin 0 of an 0 y coordinate system then the path of the projectile is y 3x x 2 1250 where x and y are measured in meters Evaluate the distance traveled by the projectile in the air

A particle moving with uniform acceleration has velocity 6 m s at a distance 5 m from the initial position After moving another 7 m the velocity becomes 8 m s The initial velocity and acceleration of the particle are O O O O 6 ms 1ms 4 ms 4 ms 4 ms 2 ms 2 ms 4 m s

Which of the following statements are not true for the motion of a body with uniform velocity O O O The motion is always in the same direction The motion is always along the straight path Average velocity of the body is equal to its instantaneous velocity Magnitude of displacement is less than the distance travelled by the body

A point starts moving in a straight line with a certain acceleration At a time t after beginning of motion the acceleration suddenly becomes retardation of the same value The time in which the point returns to the initial point is 1 2t 2 2 2 t 3 t 2 4 Cannot be predicted unless acceleration is given

From a tower of height H a particle is thrown vertically upwards with a speed u The time taken by the particle to hit the ground is n times that taken by it to reach the highest point of its path The relation between H u and nis O O 2gH nu n 2 gH n 2 u O 2gH n u O gH n 2 u