Science Buddies: "Ask an Expert"

hello

do we have a formula that make relevance between mass of the thing on the lever and shifting tip of the lever?

I don't understand your question.

Levers typically have a fulcrum and the typical equations for levers involve balancing torques. For any lever to be stationary, the sum of the torques must equal zero. Torques are distances from the fulcrum times the force applied at that distance and you have to assign a positive or negative sign so that forces trying to rotate the lever in different directions are opposite in sign.

Mass really isn't directly involved; however, weight (gravitational force acting on a mass) which is proportional to mass is a force that might be involved.

sorry, i want to understand equation of
https://www.sciencebuddies.org/science- ... M&from=TSW

Sorry, you aren't alone in not understanding that equation. The first to question it was a science teacher. I looked at it from an engineer's perspective and I don't see how it can be reduced to that result. Back in February, the Science Buddies staff was going to go back to the original submitter for more information which hopefully would be a derivation that others could analyze to understand it.

Fundamentally, this is a knife edge balance beam made out of a piece of aluminum angle extrusion. Weight placed on one end causes the beam to tip which displaces a small amount of material above the fulcrum (knife edge) by shifting it to the heavier side of the balance point. At the same time, a bigger piece of material below the fulcrum is shifted to the lighter side of the balance point. When the torque (weight of material added times the distance from the fulcrum) balances with the two displacements at the fulcrum, the bar comes to rest at some angle. The interferometer is used to measure this displacement angle which can then be used to calculate the weight of the material.

can you give me more information

noujan wrote:can you give me more information

More information specifically on what?