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Cinématique

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Lesson 31: Vertical Circles. All of the formulas and questions that we have been working with up to this point have depended on one characteristic… that the object is moving in a horizontal circle.

Lesson 31: Vertical Circles

The Centripetal Force Requirement. As mentioned earlier in this lesson, an object moving in a circle is experiencing an acceleration.

The Centripetal Force Requirement

Even if moving around the perimeter of the circle with a constant speed, there is still a change in velocity and subsequently an acceleration. This acceleration is directed towards the center of the circle. And in accord with Newton's second law of motion, an object which experiences an acceleration must also be experiencing a net force. The direction of the net force is in the same direction as the acceleration. So for an object moving in a circle, there must be an inward force acting upon it in order to cause its inward acceleration.

To understand the importance of a centripetal force, it is important to have a sturdy understanding of the Newton's first law of motion - the law of inertia. Inertia, Force and Acceleration for an Automobile Passenger The idea expressed by Newton's law of inertia should not be surprising to us. Circular Motion Force Problem: Banked Curve - Physics - University of Wisconsin-Green Bay. Homework Solutions. How Things Work (PHYS1055) / Revealing the Magic in Everyday Life (PHYS0612) Suppose you would like to buy a car for daily use.

How Things Work (PHYS1055) / Revealing the Magic in Everyday Life (PHYS0612)

To decide which car to buy, you read many leaflets about different brands of car, like the one shown on the right. However, you probably get frustrated with those keywords like horsepower, displacement, V-6 engine, ABS system, ... etc. You don't know which car is the right choice for yourself! In fact, car and driving has a close relationship with science especially physics.

For example, when people talk about time of "zero to sixty" of a car, they are actually considering the time for the car to accelerate from rest up to the speed of 60 miles per hour. Mechanics, the branch of physics investigating motion, plays an important role in understanding about the motion of car. You have to push or pull a car in order to accelerate it. Have you ever noticed any car advertisement with specifications like "this engine makes 267 pound-feet of torque at 4,300 rpm"? What happens inside a car engine? Chapter 6: Circular Motion flashcards. Banked turns. Banked turns. Graphs, errors, significant figures, dimensions and units From Physclips: Mechanics with animations and film clips. The first chapter in Physclips mechanics uses displacement-time and velocity-time graphs for a man walking in a straight line, so we'll begin with this animation.

Graphs, errors, significant figures, dimensions and units From Physclips: Mechanics with animations and film clips.

We know that this depends on the length, L – a long one swings more slowly than does a short one. It also depends on the strength g of the gravitational field – it won't swing at all without one. Does it also depend on the mass, m? On the temperature, T? Let's write for the frequency, f: f = N.La.gb.mc.Td where N, a, b, c and d are numbers, yet to be determined. The other two equations tell us that b = 1/2, and that a + b = 0, so a = −a = −1/2. Physics with animations and film clips: Physclips. Analysing video material using frame grabbing software and spreadsheet software Free video frame grabbing software can be found here: or use any other video software that allows you to move through the material frame-by-frame.

Physics with animations and film clips: Physclips.

Software that allows you to measure pixels on the computer screen can be found here: or use any other software that allows you to measure pixel dimensions on the computer screen. And if you magnify enough, you can count pixels directly. Install the software and use it to open your movie. Foucault Pendulum. Alternatively, consider the motion of a point on the earth at a place that is neither at the poles or the equator.

Foucault Pendulum

During a day, a vertical line at that place traces out a cone, as shown in the sketch at right. (If the earth were not turning, the half angle of the cone would be 90° minus the latitude.) During each cycle of the pendulum, when it reaches its lowest point its supporting wire passes very close to the vertical. So, at each lowest point of the pendulum, its wire is a different line in this cone.

This cone is not a plane, so those lines do not all lie in the same plane! For yet another argument, consider the motion of the pendulum after one rotation of the earth. (I apologise for emphasising this rather obvious point. Www.ac-grenoble.fr/comptesimbriques/disciplines/sti-indus/s-si/travaux_pratiques/tp_avidsen_traj-mvts/export/visu21.html. Www.ac-grenoble.fr/comptesimbriques/disciplines/sti-indus/s-si/travaux_pratiques/tp_avidsen_traj-mvts/export/visu21.html.