# Sand sample

1. Mar 3, 2014

### ExoP

Hi,

I was thinking of something: How are one supposed to calculate the moment needed for a scoop to scoop up a sample of e.g. sand? Does the classical p=mv work? Any ideas or comments?

2. Mar 3, 2014

### sophiecentaur

It's not clear what you mean by your question; it is clearly in a particular context.
P=mv is the momentum of a mass m with velocity v.
A certain Impulse will be needed to accelerate a mass m to velocity v and Impulse is Force times the time it is applied. A small force takes more time to do the job than a large force. I think you may be referring to Impulse rather than the "moment" (=Momentum) in your post.

If you are, in fact, scooping sand, then the scoop could provide less force over a longer time than for, as an example, a golf club, which may have contact for a small fraction of a second. These are general comments and a more useful answer could be given if there were more detail about the actual sampling job you have in mind.