How to Measure Friction Using a Spring Scale

A spring scale is a kind of spring balance weighing scale which consists of a spring fixed at one end of the device which is attached with a hook to the other end where we can attach an object in order to weigh it. This scale follows Hooke’s law according to which we can say that the force needed to extend the spring of spring scale is proportional to the distance to which spring gets extended from its initial position. Though mostly these are bought in use for industrial purposes, but they can even be bought in use to measure friction as well. Here are some tips applying which you can easily do so:-

How to Measure Friction Using a Spring Scale

1. Know what friction is:-

Actually friction is the force that resists the relative motion of solid surfaces, layer of fluids and material elements which slide against each other. When we pull an object, we can determine the force required to pull it by using a spring scale and this is the same force what we call force of friction.

2. Gather the essentials:-

In order to measure force of friction with a spring scale, you will need a spring scale, a piece of string with negligible mass, the test objects like wooden block and some additional masses etc. An area of uniform roughness should be chosen to work upon and many concordant readings should be taken in a single time. You will have to take recordings into units of mass, but you will have to convert that into the unit of force i.e. Newton.

3. Recording the mass:-

We attach the block with the help of string to the spring balance and then we note the value of its mass in a table drawn on a piece of paper. Now place some added mass say 1kg on the top of this wooden block and then pull the object using the same spring scale to take more reading/s.

4. Beginning the Approach:-

There should be no tension in the spring when you begin the approach of depicting friction with the help of spring scale. The scale should be kept at zero value before using it in order to get true force readings. Increase the force, repeat the process and take the best force reading while pulling the block and you will have the force of friction just before the point the block begins to move. This is called static force of friction.

5. Take many concordant Measurements:-

By just a few measurements, you can never say that concept of measurement of friction is clear to you but instead you will have to take at least 3-4 concordant readings and then you will have to find an average of all those values. This will be the most precise value of force of friction obtained from your experiment.

6. Record the Values and Compare them:-

Now we use the block in a way while sliding it to find frictional force needed to pull it. Here we rotate the block in such a way that its narrow side makes contact with the sliding surface and then we will again note down a few concordant values in the same way.