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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?

Slipping vs Tipping on an inclined plane

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 a

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

A car going up a hill.

(Please see attachment) A 2500 lb car has 110 hp available to maintain a speed of 60 mph up a hill. How steep a hill can it climb if wind and rolling resistance forces are 40 lbs.

A crate rests on an inclined plane (coefficient of static and kinetic friction given) and is connected to a hanging mass over a pulley. To determine tension in the rope etc..

A 14 kg. crate starts at rest at the top of a 50 degrees incline. The coefficients of friction are us=0.38 and uk=0.29. The crate is connected to a hanging 8.2 kg box by an ideal rope and pulley. (a) As the crate slides down the incline, what is the tension in the rope? (b) How long does it take the crate to slide 1.94 m down

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

String and the pulley

Attached is one problem. In the system below, the string and the pulley are massless and the coefficient of kinetic friction between m1 and the incline is 0.2. The system is released from rest and accelerates under the weight of m2. (a) draw a Free Body Diagram for each block . (b) Write down Newton's 2nd law for each bl

Explosive bolts separate a 840-kg communications satellite

Explosive bolts separate a 840-kg communications satellite from its 560-kg booster rocket. If the impulse of the explosion is 385 N/s, at what relative speed do the satellite and booster separate? vrel = m/s Please give me a stepwise solution.

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


(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

A 0.14-kg baseball with an initial speed of 28 m/s rebounds

A 0.14-kg baseball with an initial speed of 28 m/s rebounds with a speed of 34 m/s after being struck with a bat. If the duration of contact between ball and bat was 2.1 ms, what was the average force between ball and bat? I need to see each step and formula to solve this question.

Speed of a ball immediately after being struck:

A croquet mallet delivers an impulse of 8.83 N seconds to a 0.44-kg croquet ball initially at rest. What is the speed of the ball immediately after being struck? I need to see each step and formula to solve this question.

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

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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?