http://www.woodcarvingguru.com/titanium-hammer/
Momentum vs. KE?
I’m in construction, and at work one of my coworkers just bought a new hammer for a hefty price. It’s titanium, and it’s pretty lightweight (about 14 oz compared to 23 oz). So, his argument is that he can drive nails in easier because its light weight means he can swing it faster. I figure it doesn’t matter if he swings it faster. Since it’s lighter, it’ll have equal or probably even less momentum than a heavier hammer.
Having had high-school physics, i know that KE=1/2mv^2, and momentum=mv. Which would I use to figure the driving power behind a hammer? If it’s KE, then i suppose he may be correct in his thinking…
They can’t be the same significance. If you cut the mass of something in half and double its velocity, its momentum stays the same while its KE doubles…
Obviously, a nail needs energy to penetrate wood. But this doesn’t mean lighter hammer – better hummer. When one swings with a hummer, he mostly spends his energy to accelerate his hand. The hummer gets a small part of that energy. Heavier hummer gets greater part of the energy. But if a hummer grows up too much one would be spending too much energy just not to drop it.
So, for anyone there are his own best hummer weight.
I’m not an English speaker, so forgive me my rugged English.