Question

 

a) What are the possible errors /uncertainties that can occur in an Incline Friction Experiment? (as detailed as possible for this part)

b) What is the Incline Friction experiment background information (Like the method and the equipment used)?

c)What is the Theory about the Incline Friction experiment? (as detailed as possible for this part)

Answer 1

Incline friction Experiment is about finding

(i) Coefficient of friction that is experienced between the roller / block that is placed on the inclined plane when moved. The coefficient of friction is

where, h is the height inclined and b is the base of the triangle.

(ii)With the angle of inclination () and the weight (W=mg), the relationship between the downward force acting on the roller/block on the inclined plane due the gravity can be studied. and hence the downward force acting on the body of weight w=mg is found to be equal to the product of the weight of the roller and the sine of the angle of inclination , mg sin.

Cutting to the chase, let me answer you first question.

(a) The errors / uncertainties that can occur in this experiment can be sometimes with the block or the inclined plane used. Make sure that both the block and the plane are dry. If they are wet the friction experienced with both the objects can be different , thus resulting with a different coefficient of friction than that of the original.

Another error which can occur is with the strain experienced by the thread with the pulley. Make sure that the thread is straight and parallel with the inclined plane so that exact value of force can be calculated. Make sure to adjust the thread to a parallel position after each trial.

(b) The apparatus used in this experiment are an adjustable inclined plane, a roller / block attached with a pan (to add weights), a meter scale and a weight box (to add and remove weights)

(c) The theory behind this experiment is to find the  coefficient of friction that is experienced between the plane and the roller as discussed below. They could be simply calculated by the formula for   as given above.

To start the experiment, Put the block on the inclined plane and slowly increase the angle of inclination until the block just begins to move downwards. Now at this point measure the height (h) of the inclined plane and the base (b).

Add more weight, say 5 gm and increase the angle of inclination and find the point where the block just begins to move down on the plane. Now at this instant, measure the height (h) of the inclined plane and the the base again,

Repeat this procedure for each case by adding further weights and hence mark h and b in a table. Find their mean values and this would give you the value of Coefficient of friction .

To find the downward force experienced by the block on the inclined plane the value of the weight of the block and the angle of inclination can be used, Hence, downward force acting on the body is

where weight w=mg