Share
Explore BrainMass

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.

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?

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

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

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

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

Determining speed of a car after breaks are locked

At an accident scene on a level road, investigators measure a car's skid mark to be 88m long. It was a rainy day and the coefficient of friction was estimated to be 0.42. Use these data to determine the speed of the car when the driver slammed on (and locked) the brakes. (Why does the car's mass not matter?)

Newton's laws: Speed limit on highway curve

On a highway curve with radium 50m, the maximum centripedal force that can act on a 1,000kg car going around the curve is 8,000 Newtons. What speed limit should be posted for the curve so that cars can negotiate it safely?

Buoyant force: Stone dropped into sea water

A stone of density 5g/cm^3 completely immersed in sea water is allowed to sink from rest. Calculate the depth to which the stone would sink in two seconds. Neglect effect of friction. Relative density of sea water = 1.025 and g = 980cm/s^2

Centripetal Force

A "swing" ride at a carnival consists of chairs that are swung in a circle by 12.0 m cables attached to a vertical rotating pole. Suppose the total mass of a chair and its occupant is 220 kg. (a) Determine the tension in the cable attached to the chair. (b) Find the speed of the chair.