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Newton's Second Law

Applications of Newton's Law

The 65 kg man in the roller coaster car is sitting on a bathroom scale. If he is traveling at 40.4 m/s at the point shown and the radius of the vertical coaster track is 62 meters to the nearest newton, what does the scale read? What would be the answer if the roller coaster was at the bottom of the track? (See attached fi

Mass on a spring of structure-less body

Let m be the mass of a structureless body supported by a spring with a uniform force constant k . Set up the differential equation of motion that determines the displacement of the mass from its equilibrium position at time t when the intital conditions are x(0) = x0 and x'(0) = 0.

Linear Momentum and Collisions

A car with linear momentum 8.0 x 10^4 kg* m/s brakes to a stop in 5.0 seconds. What is the magnitude of the braking force?

Magnitude of the Gravitational Force

The mass of one small ball is 1.59 g, and the mass of another is 881 g. If the center to center distance between thse two balls is 13.5 cm, calculate the magnitude of the gravitational force that each exerts on the other. Please explain.

Newtons Laws and Friction with Pulleys

In the figure (see attachment) the coefficient of static friction between mass m1 and the table is 0.35, whereas the coefficient of kinetic friction is 0.25. a) What minimum value of m1 will keep the system from starting to move? m1 = ?kg b) What value of m1 will keep the system moving at constant speed? m1 = ?kg

Two Blocks and Two Pulleys System

A block of mass m_1 is attached to a massless, ideal string. This string wraps around a massless pulley and then wraps around a second pulley that is attached to a block of mass m_2 that is free to slide on a frictionless table. The string is firmly anchored to a wall and the whole system is frictionless. A) Given the magnit

Newtons Laws - centripetal force

The string of a conical pendulum is 50.0 cm long, and the mass of the bob is 0.250 kg. a) find the angle between the string and the horizontal when the tension is six times the weight of the bob. b) what is the radius of the circle in which the bob is moving? c) under those conditions what is the period of the pendulum?

Motion on an inclined plane

Determine the time time tB, tC, and tD needed for a block of mass m to slide from rest at A to points B, C, and D, respectively. Neglect effects of friction. See attachment for picture.

Coefficient of Friction for a Skier on a Hill

A skier is moving at 20.0 m/s down a 30 degree slope. He encounters wet snow and slides 145 meters before coming to a stop. What is the coefficient of friction between the skis and the snow?

Free Body Diagram

Please answer each question with step by step answers so I understand the solutions. Thanks! 1. The imperial units for mass is slugs, for length is feet and for time is seconds. The imperial units for force is a pound. What is a pound in terms of slugs, feet and seconds? 2. A box is on a sled. The sled is pulled up a hill

Application Of Newton's Second Law

A 400-kg ice boat moves on runners on essentially frictionless ice. A steady wind blows, applying a constant force to the sail. At the end of an 8.0s run, the acceleration is 0.50 m/s^2. a. What is the acceleration at the beginning of the run? b. What was the force due to the wind? c. What retarding force must be appl

How do you find the differential equation of motion?

A rope of mass M and length L lies on a frictionless table, with a short portion Lo hanging through a hole. Initially the rope is at rest. 1) Find a general equation for x(t), the length of rope through the hole. 2) Evaluate the constants A and B so that the initial conditions are satisfied

Momentum of Freight car containing a mass of sand

A freight car of mass M contains a mass of sand "m". At t=0 a constant horizontal force F is applied in the direction of rolling and at the same time a port in the bottom is opened to let the sand flow out at constant rate dm/dt. Find the speed of the freight car when all the sand is gone. Assume the freight car is at rest at

Find friction coefficient such that block m does not slip.

On a frictionless table a block of mass M=1.75 kg is attached to a spring of negligible mass whose force constant k= 60 nt/m. Riding on top of M but not attached to it, is a block m= .65 kg. The blocks execute SHM with amplitude Xm= .25 m. Find the minimum value of the coefficient of friction, u, between the two blocks, such t

Impulse concepts

Discuss the following in terms of impulse and momentum: Why are padded dashboards safer in cars? Why are nylon ropes, which stretch under stress, favored by mountainclimbers? Why is it preferrred that railroad cars be loosely coupled with slack between cars?

Newton's 2nd law

Please see the attached file for full problem description. Kathy and her friend go sledding. Out of curiosity, she measures the constant angle, , that the snow-covered slope makes with the horizontal. Next, she uses the following method to determine the coefficient of friction, k, between the snow and the sle

Nonequilibrium Applicastions of Newtons Laws of Motion

A crate is resting on a ramp that is inclined at an angle 0(thada) the horizontal.As 0(thada) is increased, the crate remains in place until 0(thada)reaches a value of 38.0 degrees. Then the crate begins to slide down the slope. (a) Determine the coefficient of static friction between the crate and the ramp surface. (b) The coef

Newton's second law and centripetal force

A small, frictionless ball, mass M= 2.5 kg, rests on the surface of a rotating solid cone. The surface is at angle b= 30 degrees. The ball is held in place at distance L= 1.85 m from the apex by a cord. The cord exerts force T on the ball, parallel to the cone's surface. SEE ATTACHMENT #1 for a diagram showing parameters. Part

Horizontal force required to set a block in motion: static and kinetic friction

A 25kg block is initially at rest on a rough, horizontal surface. A horizontal force of 75N is required to set the block in motion. After it is in motion, a horizontal force of 60N is required to keep it in motion. A. Calculate the coefficient of static friction B. Calculate the coefficent of kinetic friction C. If the or

Determining Vertical Height on Incline

A solid steel ball of radius r rolls down an incline into a loop-the-loop of radius R. What is the minimum speed the ball must have at the top of the loop in order to stay on the track? At what vertical height on the incline, in terms of the radius of the loop, must the ball be released in order for it to have the required min

Block Sliding Down a Fictionless Plane at an Angle

A 4.0 kg block is released from rest at the top of a frictionless plane of length 8.0 m that is inclined at an angle of 15° to the horizontal. A cord is attached to the block and trails along behind (assume the cord is massless). When the block reaches a point 5.0 m along the incline from the top, someone grasps the cord and e

Newton's Second Law of Motion and Gun Acceleration

Scientists are experimenting with a kind of gun that may eventually be used to fire payloads directly into orbit. In one test, this gun accelerates a 5.0-kg projectile from rest to a speed of 4.0 x 10^3 m/s^2. The net force accelerating the projectile is 4.9 x 10^5 N. How much time is required for the projectile to come up to sp

Determining Speed After Movement

See the attached file. A 5.06 kg block located on a horizontal floor is pulled by a cord that exerts a force F = 13.9 N at an angle theta = 18.0° above the horizontal, as shown in the figure. The coefficient of kinetic friction between the block and the floor is 0.06. What is the speed of the block 3.5 s after it starts mov