Question

It is always a good idea to understand the "size" of units. The objects listed below are resting on a hard surface. Categorize each object according to the pressure it exerts on the surface when placed on their side with the largest area, which is the bottom. Assume that the bottom of each object is flat and that the pressure refers to that above atmospheric pressure (that is, gauge pressure). Use common sense estimates, make your own measurements and/or do a little research to determine the relevant dimensions and weights of the objects.

Determine the Pressure of a

brick

sheet of paper

textbook

penny

can of soup

Answer 1

bscured by some scaffolding, a small white plaque says the first canned food was produced on this site. But it fights a losing battle for attention with the sign for Karma Supermarket's low-price beers, spirits and ciders - some sold in four-packs that could be described as the first cans' modern-day descendants.

Such a low-key commemoration reflects how mundane the tin can has become to us. Behind the door of a kitchen cupboard or lying discarded in the street, literally and metaphorically kicked down the road, it exists in the background of our lives.

It's a far cry from the days when its creation occupied the thoughts of some of the leading scientific thinkers in Britain and France.

So committed were these bright minds to the technology of food preservation that they gave little thought to making a device to open their new invention, so for decades a hammer and chisel, a bayonet or a rock had to do the job.

"I think Appert deserves the title because without Appert, there wouldn't have been Girard. Without Girard, there wouldn't have been Donkin, Hall and Gamble. And without Donkin, Hall and Gamble making a

success of their business there would not have been Donkin, Hall and Gamble clones and a global industry."

the British and French were not only competing at sea and on land in the Napoleonic wars, but also vying to come up with a miracle food. In Paris, a financial incentive was offered.