Newton's law of motion Questions and Answers

A particle starts from rest moves with constant acceleration for 15s If it covers s distance in first 5s the in next 10s then find the relation between s s distance 2 3 KINEMATICS 01 E

3 8 metre 4 48 metre A block of mass M is pulled by a uniform chain 12 of mass M tied to it by applying a force F at the other end of the chain The tension at a point distant quarter of the length of the chain from free end will be 1 T 3 3F 4 M M 2 4F 6F 4 7 3 8 27 MM RT 3 T F feed for at und T 3 00 4 48 T fort tem M M 4 1

A heavy uniform rod AB of weight w is hinged at A to a fixed point and rests in a position inclined at 60 to the horizontal under the action of a horizontal force F applied at the lower end B Find the force at the hinge A w 10 and squads 11 B w 13 12 C w 9 10 D w

A small ring of mass m is constrained to slide along a horizontal wire fixed between two rigid supports The ring is connected to a particle of same mass by an ideal string the whole system is released from rest as shown in the figure If the coefficient of friction between ring A and wire is the ring will start sliding when the connecting string will make an angle with the vertical then will be particle is free to move and ring can slide only A B TIITTIT ESA 45 m 30 60 m EB

5 A particle starts from rest accelerates at 2 ms2 for 10s and then moves with constant speed of 20 ms for 30s and then decelerates at 4 ms2 till it stops after next 5 s What is the distance travelled by it egon a 750 m b 800 m c 700 m vmi d 850 m

Inclined plane is moved towards right with an acceleration of 5 ms as shown in figure Find force in newton whi block of mass 5 kg exerts on the incline plane All surfaces are smooth A 50 N C 55 N 5kg 5 m s B 60 N D 70 N 37

4 On a straight highway two cars A and B are running at the same speed u 108 km h in the same lane In the best efforts of braking at this speed the car A can stop in tA 7 0 s and the car B in t B 10 s In an emergency when driver of the front car applies brakes in response the driver of the rear car also has to apply brakes to avoid accident However braking of the rear car begins after a delay ta 1 0 s from the instant its driver notices the brake light signal of the front car If car B is running ahead of car A what should be the minimum

The mud released from the wheel of a bicycle fly of tangentially and gets collected w the mud guard This is due to the principle of a a Inertia of rest b b Inertia of motion c c Inertia of direction d d Newton s third law

ppose an object is traveling at its terminal velocity so it is falling through air celerating How does the force of air resistance compare to its weight a The two forces are equal and opposite b The two forces are equal c Air resistance is greater than the ball s weight d Air resistance is less than the ball s weight

A ball is released from rest at a height of 10m on an inclined plane 3 of inclination 53 If coefficient of restitution for collision is Then 4 its total time of motion is approximately A 3 5 sec C 12 8 sec B 8 6 sec D 22 sec 10m 53

A cabinet is sliding on the inclined surface with constant velocity as shown in figure In cabinet there is a block pulley system moving with velocity same as cabinate The speed of block having greater mass w r t cabinet is 5a m s after 2s of its release Find the value of a 50 m s 50m 60 cabinet 3mm

A block of mass 1 kg starts from rest at x 0 and moves along the X axis under the action of Da force F kt where t is time and k 1 Ns The distance the block will travel in 6 seconds is A 36 m B 72 m C 108 m D 18 m

A mass of 1kg is suspended by means of a thread The system is i lifted up with an oacceleration of 4 9 ms2 ii Lowered with an acceleration of 4 9 ms The ratio of tension in the first and second case is O A 3 1 B 1 2 C 1 3 D 2 1

In a performance test each of two cars takes 9 6 s to accelerate from rest to 29 m s Car A has a mass of 1422 kg and car B has a mass of 1887 kg Find the net average force that acts on a car A and b car B during the test a F b F i 17

3 5 5 m s A body starts moving along a straight line with a constant acceleration of 10 m s2 The distance it travels in the fourth half second is 1 7 5 m 3 8 75 m 2 8 25 m 4 35 m with a uniform acceleration 1 m s and ho same

types i soldiers in a march past on a straight road ii the movement of our chest while breathin g iii hands of an athlete in a race iv pedal of a bicycle in motion v motion of earth around the sun vi motion of a swing vii motion of a pendulum viii a stone falling from a certain height ix a plucked string of a sitar x tip of the hand of a clock xi a car moving on a curved path xii motion of a train on a straight bridge xiii motion of a spinning wheel

4 0 2v2 So m 0 7v6 g 9 0 7vo 0 3v 0 0 mk 0218 0 143 9 L 10 35m gk A uniform solid cylinder A of mass m can freely rotate about a horizontal axis fixed to a mount of mass m A constant horizontal force F is applied to the end K of a light thread tightly wound on the cylinder The friction between the mount and the supporting horizontal plane is assumed to be absent Find V the acceleration of the point K b the kinetic energy of the system t seconds after beginning of motion acosm Cognitions Pvt Ltd 57 Kalu Sarai Sarvapriya Vihar New Delhi 110016 Email enquiry megacosmcognitions com website www megacosmcognitions com

An object falls freely from rest on a planet where the acceleration due to gravity is 20 m s What is its speed after 3 8 s O 144 4 m s O 19 33 m s 076m s O 5 26 m s O 3 8 m s 04 14 44 m s O 20 m s 23 8 m s O 59 72 m s O 70 22 m s

Example 1 6 A rigid insulated wire frame in the form of a right angled triangle ABC is set in a vertical plane as shown in the figure Two beads of equal masses m each and carrying charges 9 and 9 are connected by a cord of length and can slide without friction on the wires IIT JEE 1978 B 30 a 0 92 60 C Fig 1 100 Considering the case when the beads are stationary determine i the angle a ii the tension in the cord iii the normal reaction on the beads If the cord is now cut what are the value of the charges for

Calculate the acceleration of the mass 12 kg shown in the set up of fig Also calculate the tension in the string connecting the 12 kg mass Assume the string are weightless and inextensible and the pulleys are weightless and frictionless 30 9 56 g 10 5 2g 60g 4kg N 12 kg

Two masses of 6 kg and 4 kg are connected to the two ends of a light inextensible string that goes over a frictionless pulley Find the acceleration of the masses and the tension in the string when the masses are released Take g 10ms

Two strings support a uniform rod as shown String at end B is cut Which of the following is true just after cut II B P initial acceleration of A is vertical Q initial acceleration of A is horizontal R initial acceleration of centre of mass of rod is vertical S initial acceleration of centre of mass of rod is horizontal A P and Q B Q and R C R and S D P and S

A bullet of mass 10 g travelling horizontally with a velocity of 150 m s 1 strikes a statio nary wooden block and comes to rest in 0 0 3 s Calculate the distance of penetration o f the bullet into the block Also calculate th e magnitude of the force exerted by the wo oden block on the bullet

A spring of balance A is suspended vertically from a rigid support another spring balance B is suspended from the hook of A Now a weight of 2 kg is suspended from the hook of B What would be the readings of balance A and B Give Reason

6 Nathan fixed an arrangement in the lift so that to record an observation The picture shown below depicts the arrangement The velocity of the elevator is 3m s and is moving upwards The velocity of twisting of a string on the iron rod is also 3m s The rod is attached to a block A which is moving down with a velocity of 3m s For the given conditions the velocity of block B will be

a 4t m s respectively Block C is attached to massless and frictionless pulley as shown in the figure Then at time t 2 sec Initially assume system is at rest A A velocity of block C will be 25 3 m s B velocity of block C will be 30 m s C acceleration of block C will be 11m s a B

27 v t graph of an object moving along a straight line is as shown in the figure v m s 4 2 0 4 6 8 t s Acceleration of the object at t 3 sis 2 m s 4 3 m s2 2 1 m s 2 2 m s2

Physics A staircase contains three steps each 10cm high and 20cm wide What should be the minimum horizontal velocity of a ball rolling off the uppermost plane so as to hit directly the lowest plane A 0 5m s B 1m s C 2m s 3 D 4m s

The vertical section of the road over a bridge is a circle of radius 27 m A truck has its center of mass three meter above the ground If g is 10 m s then the greatest speed at which the car crosses the bridge without losing contact with the road at the highest point is 1 10 m s 3 9 8 m s 2 10 3 m s 4 8 m s

A book is sitting at rest on a table Which of the following if any is NOT an action reaction pair force of book on the table and normal force on the book force of gravity on the book due to the earth and force of gravity on earth due to the book force of gravity on the book and normal force on the book

Three identical blocks each of mass 10 kg are connected by ideal strings and are being pulled along horizontal frictionless table by a constant horizontal force F refer diagram T 120 N A B Which of the following statements are correct A Tension in the string connecting blocks A and B is 60 N B The magnitude of F is 120 N C The magnitude of F is 180 N D Acceleration of blocks is 4 m s C F

Decision 1 Colliding with the SUV 2 If the Self Driving Car collides with an SUV with the force you calculated above question 1 what force will be applied to the SUV during the collision 1 pt 3 Which of Newton s Laws best explains your answer to 2 1 pt 4 Calculate the deceleration of the Self Driving Car Sedan during the collision using Newton s 2nd Law a F m 3 pts Givens Answer Givens Work 5 Calculate the acceleration of the SUV during the collision using Newton s 2nd Law a F m 3 pts Work

Two masses of 10 kg and 20 kg respectively are connected by massless spring as shown in the figure A force of 200 N acts on the 20 kg mass At the instant shown the 10 kg mass has an acceleration of 12 m s What is the acceleration of 20 kg mass 10 Kg 1 12 m s 2 4 m s 3 10 m s 4 zero oooooooooo 20 Kg 200N

When a force F acts on a body of mass m the acceleration produced in the body is a If three equal forces F F2 F3 F act on the same body as shown in figure then the acceleration produced is F2 135 F3 A 2 1 a 90 F B 2 1 a

An ideal string is passing over a smooth pulley as shown Two blocks m and m are connected at the ends of the string If M 1 kg and tension in the string is 10 N mass m is equal to g 10 m s m m

tyre is u Find the speed at which the cal will u please tell wt is the condition required for car to Not skid Given Radius of circular road R Acceleration of car a Friction coefficient between Let m be the mass of the ca please explain the FBD There will be two compone the linear movement and the When car is moving forward how is f a acting forwards shouldn t f a be backwards as car moves front like this Balancing forces in the tangential direction we get F m ma Balancing forces in the radial direction we get F m fe te fa ar by the road ngential force f which opposes ch opposes the radial movement mg N

4 The amplitude of wave disturbance propagating in 1 1 x att 1 s where x and the positive x direction is given by y 1 time t 0 and y 1 x 2 y are in metres The shape of wave does not change during the propagation The velocity of the wave will be ms at

39 A particle of mass m is moving along the line y b with constant acceleration a The areal velocity of the position vector of the particle at time t is u 0 abt a constant b c abt 2m d 2 a bt 2m

1 The acceleration of 8 kg block just after system is released is All surfaces are smooth ideal pulleys massless strings g 10 m s 1 1 m s 3 1 5 m s 8 kg 10 kg 7 kg 5 kg 2 2 m s 4 None of these moving upwards with

2 10 2 m 4 15 m wn vertically upwards its its maximum height is height attained by it is 30 m 12 8 m H The time taken to is 2 1 er is found to 59 The velocity v of a particle moving along x axis varies with its position x as shown in figure The acceleration a of particle varies with position x as v m s 4 x m 2 1 a x 3 2 a 2x 4 3 2a 3x 5 4 a 4x 8 The velocity v time t graph for a particle moving olar The acceleration a time moving along a straight star in figure Which of the foll representation of variatin time 1 3

12 A man has fallen into a ditch of width d and two of his friends are slowly pulling him out using a light rope and two fixed pulleys as shown in figure 5 E4 Show that the force assumed equal for both the friends exerted by each friend on the rope increases as the man moves up Find the force when the man is at a depth h

12 DETAILS A locomotive exerts a constant force of 6 77 x 105 N on a train that has a mass of 1 34 x 107 kg The train is on level rails Ignore air resistance and any resistance force from the rails on the wheels of the train How much time does it take to increase the speed of the train from rest to 66 7 km h Enter your answer in minutes

ultive A disc is placed over two inclined wedges of different inclinations At some instant if velocity of either wedge is u find velocity of ob disc at that moment u 31

15 In the arrangement shown the blocks of unequal masses are held at rest When released acceleration of the blocks is m A g 2 C a value between zero and g Frictionless m B g D a value that could be greater than g

Example 5 7 Three cylinders weighting 100 N each and of 80 mm diameter are placed in a channel of 180 mm width as shown in Fig 5 16 180 mm Fig 5 16 Determine the pressure exerted by the cylinder A on B at the point of contact ti the

Blocks A and B are at rest on incline planes as shown in figure the ratio of the contact forces exerted by incline plane on blocks A and B is ift A 2 kg 37 1 1 1 3 1 4 B 53 1 kg 2 2 1 4 1 8

A bullet of mass 20 g is fired horizontally from a gun with initial velocity of 300 m s If mass of the gun is 2kg then the magnitude of final momentum of the gun is V 1 6 kg m s 3 2 kg m s 2 1 kg m s 4 0 2 kg m s

In the figure below suppose that Fw 40 N What is the value of FT1 tension 1 Consider that the ropes are massless and unstretchable a 28 N b 31 N c 34 N d 52 B e 58 N 60 FTI 70 Fw FT2

oining the masses At some instant acceleration of the block A is 5 m s left side Find the acceleration tally the spring is in natural length At t 0 F 20 N force starts acting on the block B along the line n m s2 of the block B at that instant 5 m s A m 2 kg 000000 B m 5 kg F 20 N

Jupiter s moon lo has active volcanoes in fact it is he most volcanically active body in the solar system that eject material as high as 500 km or even higher above the surface Io has a mass of 8 93 x 1022 kg and a radius of 1821 km Part A How high would this material go on earth if it were ejected with the same speed as on RE 6370 km mg 5 96 x 1024 kg Express your answer with the appropriate units h 91 65 A km BMC Submit Previous Answers Request Answer