Explore BrainMass

Newton's Second Law

The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force in the same direction as the net force, and inversely proportional to the mass of the object.

F = ma

Where force is measured in Newton’s

Newton’s second law of motion pertains to the behavior of objects for which all existing forces are not balanced. The second law states that the acceleration of an object is dependent upon two variables, the net force acting upon the object and the mass of the object.

For example, a car, which weighs 900 kg is out of gas. The driver is trying to push the car to a gas station and makes the car go 0.06 m.s^2. What is the force the driver is applying on the car?

F = 900kg * 0.05m/s^2

F = 45 N

Newton's Second and Third Law of Motion

1. Consider a plane that flies due east on a trip, and then returns due west following the same exact route. Imagine also that there are no winds in each trip. Flying due east, the plane flies with the rotation of the Earth, while flying due west, it flies against the rotation. Will the flight times be the same? Different? Why?

Newton's Laws of Motion: Slipping vs. Tipping

Please also see the attached file. The fig. shows a uniformly dense rectangular brick of length a, height b resting on a rough inclined plane of angle theta. The interface between surface and brick has associated coefficients of friction us, uk. A force F is applied as indicated. a) For F = 0, and varying theta, obtain an

Physics: Bone Stress and Ball Path

See the attached file. 1. Someone shoots a gun while holding their arm stiffly outstretched in front of them and with the back of their shoulder braced against a wall. The bullet leaving the gun has a mass of 2.5 g and is traveling at 380 m/s (.22 caliber). It reaches this velocity (from rest) in 0.0001 s. Assuming that al

block and pulley system

In the system (shown in the attachment), the block of mass M1, is on a rough horizontal table. The string that attaches it to the block of mass M2 passes over a frictionless pulley of negligible mass. The coefficient of kinetic friction µ _k between M1 and the table is less than the coefficient of static friction µ_s. a.) D

Newton's Laws of Motion: Friction

1. A father pulls his young daughter on a sled with constant velocity on a level surface through a distance of 25 m. The total mass of the sled and the girl is 45 kg and the coefficient of kinetic friction between the sled runners and the snow is .35 The force exerted by the man is applied at an angle of 30 degrees with resp

Simple Harmonic Motion and the Reference Circle

An 0.50 kg object is attached to one end of a spring, and the system is set into simple harmonic motion. The displacement x of the object as a function of time is shown in the drawing below. With the aid of this data, determine the following values. (a) amplitude A of the motion (b) angular frequency (c) spring c

Locomotive pulling 3 wagons

A locomotive is pulling three wagons along a level track with a force of 100,000 N. The wagon next to the locomotive has a mass of 80,000 kg, the next one, 50,000 kg, and the last one, 70,000 kg. Neglect friction. What is the force between the 80,000-kg and 50,000-kg wagons? 35,000 N 40,000 N 60,000 N 65

Contact force between two boxes

Three boxes rest side-by-side on a smooth, horizontal floor. Their masses are 5.0 kg, 3.0 kg, and 2.0 kg, with the 3.0-kg mass in the center. A force of 50 N pushes on the 5.0-kg mass, which pushes against the other two masses. What is the contact force between the 3.0-kg mass and the 2.0-kg mass? Choices: 0 N 1

Applying Newton's second law

1) A cannon shoots a ball at an angle  above the horizontal ground. (a) Neglecting air resistance, use Newton's Second Law to find the ball's position as a function of time. (Use axes with x measured horizontally and y vertically.) (b) Let r(t) denote the ball's distance from the cannon. What is the largest possible value

kinetic energy and potential energy

(See attached file for full problem description) 26. A block of mass m is initially moving to the right on a horizontal frictionless surface at a speed v. It then compresses a spring of spring constant k. At the instant when the kinetic energy of the block is equal to the potential energy of the spring, the spring is compress

Force with Coefficient of Friction

Find the force P necessary to push a 50.6 kg block down an incline of 32.4 degrees with an acceleration of 1.78 m/s^2. P is parallel to the incline and the coefficient of friction between the block and the incline surface is 0.805. Picture is attached.

Finding the Magnitude of Horizontal Forces

(See attached file for full problem description with diagram) --- Block A in the figure weighs w1 and block B weighs w1. The coefficient of kinetic friction between all surfaces is uk. 1. Find the magnitude of the horizontal force necessary to drag block B to the left at constant speed if A rests on B and moves with it (f

Newton's law - mechanics problem involving a frictionless pulley

(See attached file for full problem description with diagram) --- A block with mass is placed on an inclined plane with slope angle and is connected to a second hanging block that has mass by a cord passing over a small, frictionless pulley. The coefficient of static friction is and the coefficient of kinetic friction is

Pendulum tension calculation in horizontal string

A simple pendulum consists of a bob of mass 1.8 kg attached to a string of length 2.3 m. The pendulum is held at an angle of 30 Degrees from the vertical by a light horizontal string attached to a wall, as shown above. 1. Calculate the tension in the horizontal string. 2. The horizontal string is now cut close to the bob,

Centripetal Force

A roller coaster at an amusement park has a dip that bottoms out in a vertical circle of radius r. A passenger feels the seat of the car pushing upward on her with a force equal to 2.3 times her weight as she goes through the dip. If r = 29.0 m, how fast is the roller coaster traveling at the bottom of the dip?

Pulley Problem

If an object with a mass of X kg sits on a frictionless table and another object with a mass of Y kg is connected to it by a wire over a frictionless pulley, how do you calculate the acceleration of the system and how do you calculate the tension of the wire?

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

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.

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

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

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