Explore BrainMass

Newton's Third Law

For every action, there is an equal and opposite re-action.


A force is a push or a pull upon an object that will result from its interaction with another object. Whenever objects A and B interact with each other, they exert forces upon each other. A force is exerted by one object onto another object. When one object exerts a force on a second object, the second object also exerts a force on the first object. The two forces are equal in strength and in opposite directions.

For example, when you sit in our chair, your body exerts a downward force on the chair and the chair exerts an upward force on your body. There are two forces resulting from this interaction. The first force is on the chair and the second is the force on our body. These two forces are called action and reaction forces and they are the subject of Newton’s third law of motion

© BrainMass Inc. brainmass.com August 18, 2018, 6:00 am ad1c9bdddf

Physics Problem: Static and Kinetic Friction

A student pulls a box of books on a smooth horizontal floor with a force of 100 N in a direction 37.0 degrees above the horizontal. If the mass of the box and the books is 40.0 kg, what is the normal force on the box?

Components of Force

See attached file for formulas. Please complete the attached problems, providing both solutions (all steps) and answers. Object A, which has been charged to +13.0 nC, is at the origin. Object B, which as been charged to - 27.5 nC, is at (x,y) = (0.0 cm, 2.00 cm). Part A What is the x-component of the force on

Rocket Physics Launching Force

A 1 Kg rocket is launched upwards with a force of 9.8N. What happens to this rocket ? g = 9.8 m/s^2 A) Never takes off the ground B) Lifts of at a constant velocity C) Accelerates initially and then drops down D) Other E) What would happen at greater accelerations Your detailed thoughts please!

Action and Reaction Forces in Collision

Due to the drivers not paying attention, a small car and a big truck collide, both are initially moving at 5 mph towards each other. Compare the magnitude of the force the truck exerts on the car to the magnitude of the force the car exerts on the truck. Which vehicle would you rather ride in? Describe why you made your choice (

Breaking a Glass Soda Bottle: Force, momentum and pressure.

A glass soda bottle is emptied of soda and filled to the very top with water. A cork is carefully fitted into the top of the bottle, leaving no air between the cork and the water.The top of the bottle has a diameter of D_top = 2.00 cm and the bottom of the bottle has a diameter of D_bot = 6.50 cm. The glass breaks when it is exp

Dynamics : Pendulum Horizontal Position

Please see attachment for full problem description with fig. The simple 2 kg pendulum is released from rest in the horizontal position. As it reaches the bottom (vertical) position the cord wraps around the smooth fixed pin at A and continues in the smaller arc in the vertical plane. Calculate the magnitude of the force R sup

Newton's Laws of Motion

While constructing a space platform a 116kg robot finds itself standing on a 24m long 205 kg steel beam that is motionless with respect to the platform. Using its magnetic feet it walks along the beam traveling south at 2.45m/s. What is the velocity of the beam with respect to the platform as the robot walks?

tension in the string

3. Two blocks are connected by a massless string and are held in position by another massless string along a frictionless incline. Let M1 = 44.0 kg, M2 = 51.0 kg, and theta = 50°. Calculate the tension in the string connecting the two blocks. What is the tension in the string which connects mass M2 to the wall?

The Normal Force Exerted

A 33 kg crate rests on a horizontal floor, and a 77 kg person is standing on the crate. (a) Determine the magnitude of the normal force that the floor exerts on the crate. (b) Determine the magnitude of the normal force that the crate exerts on the person.

Sunglasses on dashboard

You are driving your car and set your sunglasses on the dashboard. When you make a left turn, the sunglasses go sliding off to the right. Explain.

Reading of the Scale

A dump truck is being filled with sand. The sand falls straight downward from rest from a height of 2.00 m above the truck bed, and the mass of sand that hits the truck per second is 55.0 kg/s. The truck is parked on the platform of a weight scale. By how much does the scale reading exceed the weight of the truck and sand?

Kinetic Friction for a File Cabinet and Ice Block

1. A file cabinet weighing 1500 N is at rest on the floor. The coefficient of static friction between the floor and the cabinet is 0.5. What is the minimum force required to make the file cabinet move horizontally? 2. A force of 10 N applied to a block of ice with a mass of 10 kg moves it over a factory floor with a constant

Law of inertia

Start a ball rolling down a bowling alley and you'll find it moves slightly slower with time. Does this violate Newton's law of inertia? Defend your answer.

5 Discussions on Fluid statics: Weight and Upthrust

Physics 213 class discussions Please answer each question since our teacher did a poor job of not only explaining each situation(1-5), but did not give pictures on the chalk board of forces, etc or to see what is visually going on. Please add anything to help me learn please! Choose the correct answer or state not enough

Newton's Third Law of Motion: Action and Reaction

When you lean up against a wall the wall hold you up because the wall is exerting an equal force back onto you which hold you up. Why would the result be different if you tried to lean up against a shower curtain?

Archimedes' Principal: Buoyant force

A.) Water is in the big beaker in the figure on the left. Scale 1 reads 83 newtons, scale 2 reads 677 newtons, and scale 3 reads 0 newtons. The hanging block has a density of 10 x 103 kg/m3. To the nearest tenth of a newton what does scale 1 read after the block is fully lowered into the beaker of water? b.) To the nearest te

Force Needed and Theta Degrees

Your car is stuck in a mud hole. You are alone, but you have a long, stong rope. Having studied physics, you tie the rope tautly to a telephone pole and pull on it sideways. a) Find the force exerted by the rope on the car, when the angle theta is 3 degrees, and you are pulling with a force of 400, but the car does not move.

What is the magnitude of N, the normal force?

A student of weight 656 N rides a steadily rotating Ferris wheel (the student sits upright). At the highest point, the magnitude of the normal force N on the student from the seat is 551 N. a.What is the magnitude of N at the lowest point? b.What is the magnitude of N if the wheel's speed is doubled?

Total time and the average force during the movement of a mass

On a frictionless ice a variable force P in Newtons, expressed by P= 5 + 6 t, is applied to an initially stationary block of wood to move it across the ice until its final speed is V= 25 m/sec. The mass of the wood is M= 3 kg. Vectors P and V are in the same direction. a. Find the time, in seconds, that the force is applied. b

Contact force on two blocks

Two blocks are in contact on a frictionless table. A horizontal force F is applied to M2, as shown. If M1 = 1.81 kg, M2 = 3.26 kg, and F = 5.50 N, find the size of the contact force between the two blocks. (Block M1 is touching block M2, sitting on a table.)


What forces are involved with a zipper?