Normal force Definition and 471 Threads

Homework Statement If the speed of a roller coaster at the bottom of the loop is 25 m/s, what is the normal force exerted by the car by the track in terms of the car's weight mg? Homework Equations N - mg =mv^2/r The Attempt at a Solution N=mv^2/r + mg N=m(v^2/r+ g) N=m (31.25...

Homework Statement :[/B] A girl pushes a 24 kg lawn mower as show in the figure. (figure shows a girl pushing a manual push mower. The force is going down the handle and theta is from the ground to the mower.) Force=25N and theta=34 degrees. Ignore friction. Gravity does apply at 9.8 m/s^2...

Silly question I know, but I want to just clarify this. The actual question: A 0.45kg bug is crawling to the right along a metre-stick which is resting on the edge of a desk. If the mass of the uniform metre-stick is 0.37kg, how far from the edge of the desk can the bug crawl before the...

This is a simple question that’s been plaguing me for a bit, but which doesn’t seem to have been covered in my basic physics class. Say you placed an object on a table. The object would feel a gravitational force whose magnitude is dependent upon the object's mass; however, in order for the...

Homework Statement How to know when one is suppose to add or subtract to get the normal force of an object. Homework Equations FN = Fg, FN = F sin(-) The Attempt at a Solution I believe to get the normal force of a 2 kg object when it is being pulled upwards by a force of 45...

Hi.. I am just confused normal forces. The definition of normal force is always perpendicular to the surface. But when we draw a free body diagram for a ladder lying against the wall. The normal force is like slanted towards the wall. Please explain thanks.

Hi, I'm a new member here! I don't like introductory by questions, but I think this is the best place to do it. My questions concern the normal force, Something that seems intuitive at first, but the details a little unclear. Homework Statement I'll break down my questions into parts: 1) I'm...

Homework Statement A 23 kg child goes down a straight slide inclined 38 degrees above horizontal. The child is acted on by his weight, the normal force from the slide, and kinetic friction. How large if the normal force of the slide on the child. Homework Equations Fnet=ma Fnety=ay...

I know that normal force usually equals mg on a flat surface. but how do i find Fn on a slanted surface? And also, how do i make superscripts and subscripts with alt codes (windows 7)? Also, is ma=mg i know that a=acceleration, and that's usually because of gravity. But in the book I'm...

Homework Statement Q: At a circumferential speed of 3m/s, what is the normal force exerted by the walls on a person having a mass of 70kg? givens: diameter of room is 3.1m coefficient of friction between the people and the wall is .4 Homework Equations circumferential...

I concluded that ((mv^2)/r)-(mg) was equal to the normal force but the answer says its equal to ((mv^2)/r)-(2mg). Could someone explain why to me please? "A half sphere of radius r is fixed to a horizontal floor. The inner surface is smooth. A small ball of mass m is at the bottom of the...

Homework Statement Derive the equation for the normal force (N) and the static frictional force (F) in terms of the weight (Mg). \beta is the angle of inclination. Homework Equations http://img62.imageshack.us/img62/5559/normalforcediagram.png The Attempt at a Solution - For N I...

Homework Statement An 80.0 kg student stands on a 20.0 kg platform and applies a steady downwards force of 300 N on a long rope; the rope extends up from the students hands passes over pulley#1 at the top and then under pulley #2; finally the rope is attached to the bottom of pulley #1, as...

Homework Statement A cube of side l rests on a rough floor. It is subjected to a steady horizontal pull F, exerted a distance h above the floor as shown below. As F increases, the block will either begin to slide, or begin to tip over and thus rotate. Determine the coefficient of static...

Homework Statement The coefficient of static friction between a small coin and a turntable is 0.30. The turntable rotates at 33.3 RPM. What is the max distance from the center of the turntable at which the coin will not slide? Homework Equations Fs max =μs (FN) V = ω (r) a=(V^2)...

Hello, From what I understand a car negotiating a banked cruve of angle \theta at a speed V0 does not experience a force of friction. But if the car goes to a speed higher than V0, then friction acts in the direction of the cruve. i.e. inwards And if the car goes at a speed lower than V0...

Homework Statement Can the normal force on an object ever do work on the object? Explain your answer. The answer in the textbook is: The normal force can do work on an object. For example, when you jump, you push down on the ground and the normal force pushes up on you and...

Hi guys, I am confused about how the normal force exerted on an object changes depending on the situation. Let's say an object weighs 10 N at rest. The normal force here is 10 N as well since that is by how much the object is pushing down on the surface. When someone tries to pull it...

Hi, I am doing a graph on a lab. However, I do not know what information goes where. I have a maximum friction force and normal force from my observations. The sheet tells me to make a maximum friction force vs. normal force graph. Does this mean maximum friction force is on the x-axis and the...

Homework Statement I am studying for my physics exam on tuesday and i came across this question and i am not sure why this equation was used. A bicycle and bicyclist of combined mass 62 kg go over a circular hump of radius 6.0 m at a speed of 5.0 m/s. What is the normal force on the bicycle...

This is a five part question, of which I have completed 2 parts, which I will explain below. This is a level 1 physics problem concerning centripetal motion on banked curves and the forces that apply to objects in these scenarios. PROBLEM: A car travels at a speed of 27m/s around a...

Homework Statement My teacher explained to my class that Normal force equals Force of Gravity. Given a free body diagram on a flat surface, Normal force is directed up, and Force of Gravity is directed down. Homework Equations So my teacher did the following: Fg = Force of gravity...

A motorcycle has a constant speed of 30.0 m/s as it passes over the top of a hill whose radius of curvature is 134 m. The mass of the motorcycle and driver is 333 kg. a)Find the magnitude of the centripetal force that acts on the cycle. (I found the Centripetal force by Fc=mv^2/r which is...

Homework Statement A ball whirls around in a vertical circle at the end of a string. The other end of the string is fixed at the center of the circle. Assuming that the total energy of the ball-Earth system remains constant, show that the tension in the string at the bottom is greater than the...

Homework Statement A small rock with mass 0.22 kg is released from rest at point A, which is at the top edge of a large, hemispherical bowl with radius R = 0.60 m (the figure ). Assume that the size of the rock is small compared to R, so that the rock can be treated as a particle, and assume...

Homework Statement A car drives over a hill that is shaped as a circular arc with radius 65.0 m. The car has a constant speed of 14.0 m/s and a mass of 423 kg. What is the magnitude of (a) the centripetal force on the car at the top of the hill and (b) the normal force exerted on the car by...

Homework Statement A hand presses down on a book. Is the normal force of the table on the book larger than, smaller than, or equal to mg? (m is the book mass) Homework Equations F+mg The Attempt at a Solution I want to say the normal force is equal to mg. Am i correct?

More or less just a general question. So if the normal force is pretty much the weight of the object (mass times acceleration of gravity) and then the friction is that times the coefficient? So basically weight is what causes MORE magnitude of friction? We take the force vector of gravity...

Physics HW help!? Normal Force between two objects? Hi, I've had trouble trying to gigure out this problem! I would really appreciate the help! The Problem: Three blocks rest on a frictionless, horizontal table (see figure below), with m1 = 7 kg and m3 = 12 kg. A horizontal force F = 103...

Oh hello there! I have a question about the normal force! In my mechanics class we are CONSTANTLY told that the normal force is not conservative. I don't doubt this for a second, if you imagine a ball rolling up and down an incline, the normal force is related to the velocity of the ball and...

Homework Statement Consider a small frictionless puck perched at the top of a fixed sphere of radius R. If the puck is given a tiny nudge so that it begins to slide down, through what vertical height will it descend before it leaves the surface of the sphere? Homework Equations...

Homework Statement Starting from rest, a 5.0kg block slides 2.5m down a rough 30 degree incline in 2.0s. Determine the following: A) the work done by the forces of gravity ( my answer 61.31J) B) the mechanical energy lost due to friction ( my answer 45.69 J) A) the work done by the normal...

So I was wondering what normal force exactly is and why or how it exists. Can someone help me understand it? A link to some page describing it would be great too. Thanks.:)

Homework Statement 2. Homework Equations + questions 1) Normal Force when considering mg as the vertical force, mg = N cos θ however, when considering N as the vertical force, N = mg cos θ note: θ is the same due to opposite angle which equation is correct? 2) Acceleration down...

Homework Statement You and your sled have a mass of 100 kg and starting from rest, slide down a very icy and frictionless road which is 20 degrees steep and 200 m long. a. What is your kinetic energy at the bottom of the hill? b. What is your net acceleration? c. How long does it take you...

Homework Statement a 1,000 kg car coasts into a slight dip in the road. The radius of the dip is 200-m. At the bottom of the dip the speed of the car is 10 m/s. what is the magnitude and dirrection of the normal force? Homework Equations Sum of f=ma to find acceleration. The...

why normal force always perpendicular? why doesn't be in the same direction of the affecting force? like a mass on a sliding wall why doesn't be opposite the direction of the weight?

I'd just like to say thank-you in advance for any and all answers. It is greatly appreciated. :smile: Homework Statement The 2kg ball is thrown at the suspened 20kg block with a velocity of 4m/s. If the time of impact between the ball and the block is 0.005s, determine the average...

Homework Statement A 80.8 kg man inside a 40.0 kg dumb-waiter pulls down on the rope. At that moment the scale on which he is standing reads 200N. Determine the elevator's acceleration (basically the man is inside the elevator pulling a rope that goes around the pulley, which makes the...

Homework Statement A 5.4g mass is released from rest at C which has a height of 1.2m above the base of the loop-the-loop and a radius of .36m Finde the normal force pressing on the track at A, where A is at the same level as the center of the loop. Answer in units of N So the picture is of...

Homework Statement A curve of radius 139 m is banked at an angle of 11°. An 866-kg car negotiates the curve at 89 km/h without skidding. Neglect the effects of air drag and rolling friction. Find the following. (a) the normal force exerted by the pavement on the tires Homework Equations...

If I have an extended (uncoiled) rope sitting on a table, and part of it is hanging off the edge of the table so that it starts to slide (there is friction), how would the normal force of the table acting on the rope change as it slides off? This has been bugging me for weeks, because people...

Homework Statement If a box that weighs 536N is pulled forward at a constant speed by a force of 150N at an angle of 37 degreees with the ground, what normal force does thte box exert on the supporting surface? ( I am really not sure at all where to begin) formula?

whenever 2 bodies are in contact , why do they exert force normal to each other on each other , i mean the normal force .

Q:Astronomers have found a new planet in our solar system and have decided to call it planet angeles. Planet angelees has only one moon. Planet Angeles mass is 90 times more massive than its moon. The center to center distance between angele's and its moon is 7.90 x 108 m. How far from the...

Block M(15.7kg) is on a horizontal table initially moving to the left because it is connected to a mass m(8.2kg) hanging vertically off of the edge of the table (left hand side of the table). A force F, with a magnitude of 75.3N, acts on M directed at an angle of 35.0 degrees above the...

Homework Statement Elevator cabs A and B are connected by a short cable and can be pulled upward or lowered by the cable above cab A. Cab A has mass 1700 kg; cab B has mass 1300 kg. A 12.0 kg box of catnip lies on the floor of cab A. The tension in the cable connecting the cabs is 1.91×10^4...

A rope of length L sits at rest on a horizontal table with length L/3 hanging over the edge. The rope is mass M. What is the normal force acting on the rope? (I keep having people tell me that it is the product of the mass of only the rope that is on the table with the acceleration due to...

A 5.0 kg mass is suspended by a string from the ceiling of an elevator that is moving upward with a speed which is decreasing at a constant rate of 2.0 m/s in each second. What is the tension in the string supporting the mass? -I know that the Normal Force on the string is Fn=mg so it...

Homework Statement "A box initially moving at 3.00m/s on a rough, level floor comes to a stop after sliding 6.00m. Find the coefficient of kinetic friction between the box and the floor."Homework Equations Fk=\mukFN V2-V02 / 2x = aThe Attempt at a Solution The first thing I did was write down...