Newton's Second Law, Gravity and Friction Forces

Demonstration Video

Audience: Instructor Student
Version: Interactive Non-Interactive

Calculation of gravitational constant, with accompanying apparatus model.

What it shows

The gravitational attraction between lead spheres. The data from the demonstration can also be used to calculate the universal gravitational constant G.

Orbital motion simulated by ball rolling on wooden potential well.

What it shows:

Motion in a central potential is demonstrated by a ball rolling on a circular 1/r curved surface.

How it works:

The 1/r potential well simulates the gravitational potential...

A physical pendulum with two adjustable knife edges for an accurate determination of "g".

What It Shows

An important application of the pendulum is the determination of the value of the acceleration due to gravity. By adding a second knife-edge pivot and...

Falling in an evacuated tube at the same rate.

What it shows:

In the absence of air resistance all bodies, regardless of size or weight, fall with the same acceleration at the same point above the Earth. Here a feather and a dime (see Comments) fall under...

What it shows:

Allow a board to rotate under the force of gravity and the free end will accelerate at a rate greater than g. Relation between angular acceleration and linear acceleration seems to give free-fall paradox.

How it works:

If a board, held in a...

The tension force in a rope grows exponentially with the number of turns the rope makes around a pole.

What it shows:

Many people have probably observed that, by wrapping a rope around a post, a person can hold in check a much larger force than would...

Apple electronically released from platform; fall time given by special circuit and digital display.

What it shows:

This is a free-fall-from-rest experiment in which an apple (or any other object of comparable size) is dropped from the lecture hall ceiling...

Straight and cycloidal inclined paths, with the ball on the cycloidal path always beating the straight one to the bottom.

Prediction of motion of masses in a more complex pulley/mass assembly.

What it shows:  This compund Atwood's Machine demonstrates an old and interesting problem. The two small weights on the right side are not of equal mass — one is 100 g and the other is...