Question

There is a lab about static equilibrium. I was told to calculate the mass of the bar on which the hanging weight is, with the formula m= 2C/ g (c is the y intercept, which is 0.07171). The question the teacher asked was 'the mass of the bar is in kilograms. How would you explain this?' On the graph the y axis is FT sin θ, so wouldn't the y-intercept have the same unit?

Answer 1

The formula for the mass of the bar was  , where "C" is the y intercept. (Note- "g" is the gravitational constant i.e., )

And you are right to point out that the y-axis had , which is force and so the y intercept "C" would have the same unit (Newtons). But then you also have to take into consideration the unit of "g".

So,  . Hence, this is the reason why you get "m" in kilograms.

For reference, .