Lab on Centripetal Force

Introduction:

A centripetal force acts on a moving object at an angle to the direction of motion, tending to make the body follow a circular or curved path. The force of gravity acting on a planet in orbit is an example of a centripetal force and the friction of the tires of a car making a turn similarly provides centripetal force on the car. In this lab we demonstrated an example of centripetal force by whirling a stopper around at the end a weighted line.

A centripetal force results from a multiplication of a mass and acceleration. The force is also dependant on the radius of the circle being formed. The object forming the circle with its path is always accelerating. We can say that this object is always accelerating because it always changing velocity as it continues in a curved path.

Methods and Materials:

We started this lab by first measuring the mass of the stopper and we made sure that the length of the strong connecting the stopper to the end of the glass tube was .8 meters long. We measured from the middle of the stopper to the end of the glass tube and we attached an alligator clip to the end of the glass tube. We then measured the mass of four washers and found the mass to be 28 grams. We then attached these four washers to the end of the line so that they could hang freely. Someone in our group then grasped the line by the glass tube and whirled the stopper over his head. We made sure that the alligator clip was about 1 inch away from the bottom of the glass tube. We used a stopwatch to time the stopper as it made 10 rotations. We recorded the time and then did this 2 more times and found an average time. We added four more washers and added them to those already on the line and we then we re-spun the line and did so until there were 32 washers on the line.