# Practical Write up of Centripetal Force

Essay by beach_bunnyHigh School, 11th gradeA-, August 2006

Centripetal Force

Background Theory:

Centripetal force is the force required to keep an object moving in a curved or circular path. It is directed inwards toward the center of the curved path. In this experiment, the mass of the revolving object and its radius of motion are kept constant. The centripetal force is provided by the weight of the slotted masses and is varied by adding more or less mass to the carrier. The frequencies corresponding to the different centripetal forces are measured and the results plotted on a graph.

Aim:

To investigate the relationship between the centripetal force acting on an object moving in a circle of constant radius and its frequency of revolution.

Materials:

Thin PVC pipe (20cm long, no sharp edges)

1.5 m length of string

Alligator clip

Large 2-hole rubber stopper

Mass carrier and slotted masses (50 g each)

Stopwatch

Metre ruler

Graph paper

Method:

1. One end of the string was securely tied to the rubber stopper. The line was then passed through the tube and attached to the 50 g mass carrier. An alligator clip was then attached to the line so as to set the radius of the circular path of the stopper to 100cm. Then five 50 g masses were added to the carrier making a total mass 300 g.

2. The stopper was then spun around a person's head in a horizontal circular path, at a speed fast enough that the alligator clip was pulled up to the lower end of the PVC pipe without touching it. This speed was maintained at the same position for the time that was taken to measure 30 revolutions of the stopper. The time taken was attained using a stopwatch. Record time taken in a table.

3. Another 50 g mass was then added to...