# Jumping on a top pan balance.

In summary, the pan balance measures the force. So if I jump(or fall from a height) on it, the force is greater because of the impact.

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A top pan balance measures the force.So if I jump(or fall from a height) on it,Why does it show a greater value?(Acceleration and mass does not change,so the force is same)??

When you jump and approach the balance you gain a velocity.When you fall on the pan all of your velocity becomes zero which means your momentum has changed.Applying conservation of momentum the momentum is transferred to the pan and as we know change in momentum over an interval of time causes a force.So then the pan would experience the gravitational force as well as the force caused due to change in your momentum

It shows a greater value because the force of impact is in addition to the weight of the object. The weight is the force it takes to keep you standing there motionless. The force of impact is the force it takes to slow you down from your falling speed to a stop on top of the force needed to keep you there.

The larger your momentum before impact, the larger your force of impact, and the greater the value the scale will show.

Oh,Momentum.Maybe I'll learn it later. :)

Oh,Momentum.Maybe I'll learn it later. :)

momentum is nothing but M*V(mass times velocity).The second law of motion itself states that force is the rate of change of momentum.How can you know about force but not about momentum?

A lot of the time the net force on an object is taught as equal to its mass times the derivative of its velocity instead of derivative of mass times velocity, especially at freshman level physics.

Momentum is more than just total of M*V. It is, "The thing which is conserved because of Newton's third law". Light has momentum, but we wouldn't describe its momentum as M times V.

jfizzix said:
A lot of the time the net force on an object is taught as equal to its mass times the derivative of its velocity instead of derivative of mass times velocity, especially at freshman level physics.

Momentum is more than just total of M*V. It is, "The thing which is conserved because of Newton's third law". Light has momentum, but we wouldn't describe its momentum as M times V.

Yeah momentum is M*V/√(1-V^2/c^2) .So you expect a freshman level physics student to understand that and about how photon has momentum but can't expect him to know that force is the rate of change of momentum.ok :uhh:

quawa99 said:
Yeah momentum is M*V/√(1-V^2/c^2) .So you expect a freshman level physics student to understand that and about how photon has momentum but can't expect him to know that force is the rate of change of momentum.ok :uhh:

Momentum is not just $\frac{M\vec{v}}{\sqrt{1-\frac{v^{2}}{c^{2}}}}$ either. Certainly not for a (massless) photon in any case, but that's beside the point.

The point is that momentum is a thing that is not defined by its experessions, but by its total value being conserved via Newton's third law. That where the expressions come from.

Also, for goodness sake, it's barely two weeks into the semester. When I was a freshman in physics I couldn't say I understood much of anything only two weeks into the class. Everyone learns it for the first time somewhere.

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In the freshman physics curriculum, usually momentum conservation is taught (just) after Newton's second law, which is why $\vec{F}=m\vec{a}$ is more ubiquitous than $\vec{F}=\frac{d\vec{p}}{dt}$ (among other reasons).

## What is a top pan balance?

A top pan balance is a type of weighing scale that has a flat, circular pan on top where objects are placed to be weighed. It is commonly used in laboratory settings to measure the mass of various substances.

## Why is jumping on a top pan balance not recommended?

Jumping on a top pan balance is not recommended because it can damage the delicate internal components of the balance, affecting its accuracy and potentially causing it to malfunction. Additionally, it can also be dangerous for the person jumping and others nearby.

## Can jumping on a top pan balance affect its calibration?

Yes, jumping on a top pan balance can affect its calibration. The force from jumping can cause the balance to become misaligned, resulting in inaccurate measurements. It is important to handle a top pan balance with care to maintain its calibration.

## What are the potential risks of jumping on a top pan balance?

Jumping on a top pan balance can cause physical harm to the person jumping and others nearby. It can also damage the balance itself, affecting its accuracy and potentially causing it to break.

## Are there any alternative ways to check the accuracy of a top pan balance?

Yes, there are alternative ways to check the accuracy of a top pan balance. These include using calibrated weights, performing regular calibrations, and ensuring the balance is placed on a level surface. Jumping on the balance is not a recommended method and can cause harm to both the balance and the person jumping.