Newton's law of motion Questions and Answers

In the adjacent figure a wedge B of mass 2m is lying at rest on a horizontal surface The wedge has a cavity which is the portion of a sphere of radius R A small sphere A of mass m is released from the top edge of the cavity to slide down All surfaces are smooth Point A is at the same height as centre of cavity Choose the correct option s S B The maximum speed acquired by the sphere is 4gR 3 The maximum height from the bottom of the circular path to which the sphere will rise after breaking off the wedge is 10R 11 The wedge will acquire its maximum speed when the sphere is about to leave it gR

Two masses of 1 kg and 5 kg are attached to the ends of a massless string passing over a pulley of negligible weight The pulley itself is attached to a light spring balance as shown in figure The masses start moving during this interval the reading of spring balance will be wwwwwwwwww O more than 6 kg O less than 6 kg O equal to 6 kg O none of the above 1kg 5kg

1 A body of mass 2 kg moving on a horizontal surface with an initial velocity of 4 m s comes to rest after 2 sec If one wants to keep this body moving on the same surface with a velocity of 4 m s the force required is 8 N 2 4 N 1 Tu 3 zero 4 2 N

5 For the given figure two blocks of equal mass m are connected by a light string that passes over a smooth pulley The block A is connected by spring constant k Initially spring is relaxed Then the block A is slowly pulled down a distance x and released The magnitude of accelerations of the left and the right blocks and az immediately after releasing are a respectively 19 A m E 0000 m B Now choose the correct options a a a b a a if ks 2mg

A basket and its contents have mass M A monkey of mass 2M grabs the other end of the rope and very quickly almost instantaneously accelerates by pulling hard on the rope until he is moving with a constant speed of Vm r 2ft s measured relative to the rope The monkey then continues climbing at this constant rate relative to the rope for 3 seconds How fast is the basket rising at the end of the 3 seconds Neglect the mass of the pulley and the rope given g 32ft s 0 4ft

A rough vertical board has an acceleration a such that a 2 kg block pressing against it does not fall down For this situation the possible value of the coefficient of friction between the block and the board can be g acceleration due to gravity at 1 2g a 2 kg 2 g 2a 2a mu 913 P P

D The two wires shown in figure are made of the same material which has a breaking stress of 8 x 108 N m The area of cross section of the upper wire is 0 006 cm2 and that of the lower wire is 0 003 cm2 The mass m 10 kg m 20 kg and the hanger is light The maximum load that can be put on the hanger without breaking a wire is 1 14 kg www EA 2 1 4 kg

Two spheres having masses m and m are kept on an inclined plane as shown Both of them are in equilibrium What is a necessary condition for this 44 is coefficient of friction between m and inclined plane and u is coefficient of friction between m and inclined plane 1 m m O 2 m m2 m m 3 m m 4 m 2 m

is zer 3 Direction of IR remains unchanged and VR is maximum at t 0 5 4 At t 0 25 direction of IR reverses and VR is maximum A 60 HP electric motor lifts an elevator having a maximum total load capacity of 2000 kg If 9 the frictional force on the elevator is 4000 N the speed of the elevator at full load is close to 1 HP 746 W g 10 ms 2 1 1 7 ms 1 3 1 9 ms 1 2 2 0 ms 1 0 4 1 5 ms 1 1 3 If we n compou and an length 1 22 3 3

on a horizontal surface The 5 0 kg block is pulled to the right with a force F as shown in Fig 39 The coefficient of static friction between all surfaces is 0 60 and the kinetic coeffi cient is 0 40 a What is the minimum value of F needed to move the two blocks b If the force is 10 greater than your answer for a what is the acceleration of each block 3 0 kg 5 0 kg F

140 g baseball is moving horizontally to the right at 40 s when it is hit by the bat The ball flies off to the left at m s at an angle of 25 above the horizontal What is the magnitude of the impulse that the bat delivers to the ball Express your answer to two significant figures and include the appropriate units J Submit Part B HA Value Ti Request Answer Units What is the direction of the impulse that the bat delivers to the ball Express your answer to two significant figures and include the appropriate units A

A uniform rod AB of mass 5 kg and length 10m is hinged at A A block of mass 10 kg is hanging with a string and other end of the string is attached to a middle point of the rod passes over a smooth pulley as shown in the figure Find the value of cos 0 2 10 kg A 5 m 0 10 m

32 A mass m is supported by a massless string wound arou a uniform hollow cylinder of mass m and radius R If t string does not slip on the cylinder with what accelerati will the mass fall or release JEE Main 201 a 6 2g 3 g N 1020 2 5g 6 c d g A blod C m R m

A particle is moving with a uniform speed in a circular orbi of radius R in a central force inversely proportional to th nth power of R If the period of rotation of the particle is I then JEE Main 2018 a To R 2 for any n 6 c Tx R n 1 2 b To Rn 2 1 d To Rn 2

d It hits the gro 4 ms 13 Three masses of 1 kg 6 kg and 3 kg are connected to each other with massless strings and are placed on a table as shown in figure 6 kg T 1 kg 10 m s the If g system is moving is a 6 ms2 c 1 ms2 3 kg acceleration with which the b 2 ms2 d 4 ms 2 tal nine 20

Two blocks of masses 7 kg and 5 kg are connected by a rope of mass 4 kg The system is pulled up with a force of 240 N as shown in figure The tension in the rope at its midpoint A is a 105 N c 240 N b 270 N d 50 N UP CPMT 2401 7 kg 5 kg