Newton's law of motion Questions and Answers

58 For the system shown in Initially the system is at rest in equilibrium condition If the string joining m and ground is cut then just after the string is cut eeeeee M eeee ma Ground Fig 6 339 Statement I m m m3 remain stationary Statement II The value of acceleration of all the four blocks can be determined m4 Statement III Only m4 remains stationary Statement IV Only m accelerates Now choose the correct options a All the statements are correct b Only I II and IV are correct LIT

A block placed at the bottom of rough incline is projected upwards with some initial speed Calculate the retardation of the block while moving up of 1 g sine ucos 0 2 g sine cos 0 3 g ucose sin 0 4 g usine cos 0 C

the tension in the string in situation as shown in the figure below Forces 120 N and 100 M tacting when the system is at rest and the maximum value of static friction on 10 kg is 90 that on 20 kg is 60N 120 N 10 fm 90 N 20 f 60 N 100 N

3 1 6 13 If in case A elongation in wire of length L IS then for same wire elongation is case B will be I WIL 1 2l 3 3l MM 2M 3M B 2 5l 4 2 4l Tz 2x3M X2N 1240 2 g

22 Two blocks of masses m and m are kept touching each other on an inclined plane of inclination a with the horizontal Show that i the force of interaction between the blocks is cos a H H mm g m m and ii the minimum value of a at which the blocks just start sliding is a tan HjM H m m m Where and 14 are the coefficients of friction between the block m and the inclined plane and between the block the inclined plane respectively m and

2 If system of blocks as shown in the figure is at rest the mass of block B is g 10 m s m 5 kg A 77777 1 m 2 5 kg 3 m 2 5 kg 0 5 1 1 B m 2 None 4 m 2 5 kg

In the arrangement shown in the figure the masses m of the bar and M of the wedge as well as the wedge angle a are known The masses of the pulley and thread are negligible Friction is absent Find the acceleration of the wedge M m a M

Two pith balls carrying equal charges are suspended from a common point by strings of equal length the equilibrium separation between them is r Now the strings are rigidly clamped at half the height The equilibrium separation between the balls now become NEET 2013 A r 1 2 2 3 2r 3 2 y 2 2r 2 6 3 1 4 2

A ball of mass m is suspended by a light thread attached to the hook of a car Fig 1 42 At the pre cise moment when the car began to descend a smooth inclined plane under gravity the thread was perpendicular to the plane When the car begins to descend what angle will the thread make with the plane The angle of inclination a m

kg s A body is launched from the earth s surface at an angle a 30 to the horizontal at a 1 5 GM Neglecting air resistance and earth s rotation Find the height to which the body R will rise Here M is mass of earth and R the radius of earth Problem 183 speed vo tollita is revolving in a circular orbit of radius a with velocity v A gun und from the gun with muzzle veloci

Q22 A block of mass 4kg is suspended through two light spring balances A and B Then A and B will read respectively A 4 kg and zero kg C 4 kg and 4 kg mmmmmm 4kg B B Zero kg and 4 kg D 2 kg and 2 kg

Car A moving along a straight horizontal road with a velocity 60 km h 1 is followed by car B moving with a velocity 70 km h When car B is at a distance 2 5 km from car A car car B applies a retardation of 20 km h 2 Where and when will the two cars meet 32 5 km h

A string passes over a weightless pulley and has two weights of 1 kg and 4 kg tide at its two ends The pulley is hung from the hook of a spring balance When the attached weights start moving due to the action of grav ity what will be the reading on the spring balance Ans 3 2 kg

3 53 33 A monkey of mass 20 kg climbs on a rope which can stand a maximum tension of 300 N In which of the following case will the rope break The monkey 1 Climbs up with an acceleration of 6 m s2 2 Climbs down with an acceleration of 4 m s 3 Climbs up with a uniform speed of 5 m s 4 Falls down the rope nearly free under gravity of Newton s second law is

In which of the following cases would the weight of a body as recorded by a physical beam balance be greater than the true weight of the body 1 In an elevator accelerating upwards 2 In an elevator accelerating downwards 3 In an elevator moving up with constant speed 4 None of the above

A box with a mass of 14 kg is resting on a ramp that is inclined at an angle of 20 Determine the magnitude of the force parallel to the ramp that keeps the box at rest 1 decimal place

2 Find the tension in each rope Assume frictionless surface 10 pts 30 10 kg 20 kg

Henry whose mass is 95 kg stands on a bathroom scale in an elevator The scale reads 830 N for the first 2 6 s after the elevator starts moving then 930 N for the next 2 6 s Part A What is the elevator s speed 5 2 s after starting Express your answer with the appropriate units V Part B HA Value Submit Request Answer upward m s What is the direction of the elevator s velocity 5 2 s after starting

Please use the interactive area below to draw the Free Body Diagram for the block Ftotal x neg F total y pos Fs 0 m Fn a F F a

27 m along level ground The total weight of sled and load is 12 000N The tractor exerts a constant 6000 N force at an angle of 35 0 above the horizontal There is a 3500 N friction force opposing the sled s motion Oto Which free body diagram corresponds to the description of the problem O O O O

Spring Forces Practice Problems Physics 1 What is the spring constant of a spring that stretches 25 cm when a 7 8 kg monkey hangs from it 76 516 281 F 76 518N h 25 723 306 07 fw n 19 1 42 3m 4 8 2 A spring has a spring constant of 45 N m What is the mass of an object that stretches the spring 0 94 m when it is hung on it on Earth F 45o 1 94h Fs 42 3 N M 4 31119 4 3 9 3 A Jack In The Box is built around a spring with a spring constant of 70 N m How hard does the spring push when you compress it from 40 cm long down to 15 cm long W m m 4 A hanging chair is suspended on a spring from the ceiling The 5880 N m spring stretches from 15 cm long to 25 cm long when you sit in the chair a How hard is the spring pulling to lift you b How hard does gravity pull down on you c How massive are you 5 Nick a 60 kg physics student wants to go bungee jumping but doesn t have a bungee cord He finds a 15 m long strong spring with a spring constant of 60 N m in his garage which he decides should work just as well He takes the spring to a nearby bridge attaches one end to the bridge and the other to his leg and jumps off After bouncing around violently for a while he finally comes to rest How far below the bridge is he hanging 5 If she hangs a 2 kg picture beneath the first one how long will the spring get Mollie is using springs to hang art projects I m not sure why Ask her She hangs a 3 0 kg picture on one particular spring and it stretches from 30 cm to 45 cm long a What is the spring constant for that spring

10 0 points Joe pushes down the length of the handle of a 12 8 kg lawn spreader The handle makes an angle of 45 4 with the horizontal Joe wishes to accelerate the spreader from rest to 1 33 m s in 1 6 s What force must Joe apply to the handle Answer in units of N

applied to it for 7 seconds What is the car s final momentum 2 A projectile is launched horizontally from a height of 40 m How long does it take the projectile to land 3 A 1 6 kg ball is dropped from a 4th story window 15 m high onto the sidewalk below How fast is the ball going right when it hits the sidewalk 4 A 2900 kg car speeds up from 5 m s to 20 m s in a time of 8 seconds What was the average force acting on the car during this time 5 A 1 kg projectile is launched with 500 J of kinetic energy How much kinetic energy does it have when it reaches a height of 10 m

1 How are forces related to motion How are forces related to energy and momentum

In the overhead view of the Figure a 300 g ball with a speed v of 10 0 m s strikes a wall at an angle 0 37 and then rebounds with the same speed and angle It is in contact with the wall for 10 ms Calculate 14T a the impulse on the ball from the wall and b the average force on the wall from the ball

f m 0 1 If a net force of 25 0 N acts on a 6 50 kg object What is the acceleration of the object Show your work below PHY1053L Newton s 2nd Law Pre laboratory Assignment 2 Suppose that m 0 450 kg block is attached to a mass of m 0 0400 kg as shown in the above figure Solve for the acceleration a of the system Show your work below p2

Free body diagram FN mig T m29 m 1 If a net force of 25 0 N acts on a 6 50 kg object What is the acceleration of the object Show your work below

A 3 0 x 103 kg truck moving at 21 m s N collides with a 1 0 x 10 kg car initially at rest The collision slows the truck to 11 m s N a What is the velocity of the car after the collision 2 b Is this collision elastic or inelastic Show calculations to support your answer 2 If the contact between the car and collision lasted 0 05 s what is the average force applied by the truck on the car 2

Brianna starts a lawnmower moving across the yard by applying a force of 75 N on the handle of the mower According to Newton s third law the handle pushes back on Brianna with 75 N of force Why don t the forces cancel each other out since they are equal but in opposite directions

What is Newton s First Law of Motion Give an example What is Newton s Second Law of Motion Give an example What is Newton s Third Law of Motion Give an example

an automobile collision a 44 kg passenger moving at 15 m s is brought to rest by an air bag during a 0 10 secon time interval Is the net force on the passenger as he slows down A Greater than 440 N B Less than 440 N C Equal to 440 N Answer Justification

13 Determine the tension in the rope when the hanging mass is 10 g Report your answer to at least three decimal places Hide Hint Hint Start by finding the net force acting on the hanging mass How much tension does the rope need to have to produce that net force

A 6 0 kg bowling ball moving at 3 5 toward the back of the alley makes a collision head on with a stationary 0 70 kg bowling pin If the ball is moving 2 77 toward the back of the alley after the collision what will be the velocity magnitude and direction of the pin

Problem 2 A uniform ladder of mass m 5 kg and length 4 m makes an angle 60 with the ground Since the ladder is barely not slipping at its base the maximum static friction force Ffrics sNgr acting on the ladder where Nground is the normal force acting on the ladder from the ground There is no friction between the wall and the ladder What is us the static friction coefficient between the ladder and the ground ground is Nground Nwall mg Ms 0

7 7XF T rF sin 0 r F TF Problem 1 A uniform horizontal beam of mass M 6 3 kg and length 6 m is attached to a wall by a hinge Its far end is supported by a cable that makes an angle of 0 30 with the beam and it provides a tension T A box of mass m 2 1 kg also hangs from the beam The box of mass m is a distance of 5 m to the right of the hinge a What is the tension T in the cable b What is N the horizontal component of the force the hinge or pivot exerts on the beam c What is N the vertical component of the force the hinge or pivot exerts on the beam Ny Nx T M 6m 5m 0

35 0 1 35 m 1 70 m Paul s Auto Repair 1 80m B 000 Problem 1 A shop sign weighing 25 kg is supported by a uniform 15 82 kg beam as shown in the figure above on the left The beam is supported by a tension T provided by a cable that makes an angle of 35 with the beam a What is the tension T in the cable Answer 708 1 N b What is N the horizontal component of the force the hinge or pivot exerts on the beam Answer 580 0 N c What is Ny the vertical component of the force the hinge or pivot exerts on the beam Answer 6 1 N downwards

FD 3 2 m 1990 CM 10m 10m X 40m Mg B Problem 3 The forces acting on a 67000 kg aircraft flying at constant speed are shown in the figure above on the left The engine thrust F 500 000 N acts on a line 1 6 m below the center of mass CM The lift force Fr acts at a distance of 3 2 m to the right of the center of mass CM a Determine the lift force F Answer F 656 600 N b Determine the drag force Fp and the distance y above the CM that the drag force FD acts on the plane Answer FD 500 000 N and y 2 6 m Problem 4 A 60 kg painter is on a uniform 25 kg scaffold that is supported above by two ropes see the figure above on the right There is a 4 9 kg pail of paint to one side How close to the left end of the scaffold can the painter get before the scaffold tips over In other words what is z as shown in the figure above on the right Hint The value of a must be less than 1 0 m Thus the painter will be to the left of the rope on the left Also the scaffold will tip over when the tension from the rope on the right is 0 Answer 0 085 m

In curling you will often see one curling stone hit another and come to rest while the stationary stone moves away from the one dimensional collision Explain how this can happen K U

1 point If you push a box in space with a mass of 45 kg and it has an of 9 m s 2 what is the force onthe object acceleration T

Write Law One Two or Three for each example a A canon recoils after being fired b Passengers lurch forward in their seat after the brakes are slammed on c Large trucks require larger engines d This law allows rocket ships to move in outer space e When you hit a desk you hurt your hand f A book will not move till you push or pull it

20 A big block of mass M is attached via a string to a smaller block of mass m A student attaches a string to block M and pulls everything to the right along the rough surface Both blocks travel at constant velocity Do force diagrams for each block separately

3 A 0 40 kg cue ball makes a glancing blow to a stationary 0 30 kg billiard ball so that the cue ball deflects with a speed of 1 2 m s at an angle of 30 0 from its original path Calculate the original speed of the cue ball if the billiard ball ends up travelling at 1 5 m s T I 5 marks

3 The ballistic pendulum used to be a common tool for the determination of the muzzle velocity of bullets as a measure of the performance of firearms and ammunition nowadays the ballistic pendulum has been replaced by the ballistic chronograph an electronic device The ballistic pendulum is a simple pendulum that allows one to record the maximum swing angle of the pendulum arm caused by the firing of a bullet into the pendulum bob Let L 1 6 m and mA 5 5 kg For a certain historical pistol which fired a roundball of mass MB 91 g it is found that the maximum swing angle of the pendulum is 52 Determine the pre impact speed of the bullet B T6 C4 L Br 0

5 A 15 0 kg penguin waddling east at a velocity of 7 0 m s collides with a stationary 10 0 kg penguin After the collision the 15 0 kg penguin is traveling at a velocity of 4 2 m s 20 0 S of E a What is the velocity of the 10 0 kg penguin after collision b is this collision elastic or inelastic 5 1 m s 25 N of E Inelastic Ex loss of 110J

A mass m is suspended by two strings as shown T and T are the unknown tensions in the strings One of the strings is horizontal and the other makes an angle with the horizontal as shown What is the tension T3 T Tz wit T3 e

Three cars car F car G and car H are moving with the same velocity when the driver suddenly slams on the brakes locking the wheels The most massive car is car F the least massive is car H and all three cars have identical tires Which car travels the longest distance to skid to a stop O Car F O Car G O Car H They all travel the same distance in stopping O can t be determined from the given information

A student puts two dynamics carts with a speed bumper between them on a track and presses them together The total mass of the carts is 3 0 kg Once the student releases them the carts spring apart and roll away from each other One cart has a mass of 2 0 kg and a final velocity of 2 5 m s S Calculate the final velocity of the other cart T covered T

Two boxes are on an icy frictionless horizontal surface You push one box which collides with the other If the boxes stick together after the collision which of the following is conserved in the collision Explain your reasoning Ku a momentum 1 Irinetic energv

A cart is propelled by a fan n The cart has a mass of 0 58 kg It took 5 s for the cart to travel 1 m starting from Calculate the acceleration of the cart Calculate the force from the fan

A leftward moving car is speeding up The Force Diagram is shown What will the Force Diagram look like if the driver eases off slightly on the gas pedal and maintains a constant speed Current State Fapp Fnorm Fa Fa air grav New State Tap here to view the answer choices Once you ve made your choice tap the Check Answer button Student Name AdameAlv Guadalup971 s nt wuhsd org Level Master 1 5 Progress Report 2 6 3 Tap for Question Specific Help Help Me