Question

1)calculate the pressure, expressed in pascals, that the brick exerting a force of 18N, and dimensions od 9.3cm x 5.5 cm.

I know that Pressure = force divided by the area. the answer I got was 0.4Pa.
Is this correct?

2) why is an ax more useful to use (in terms of pressure) than a hammer, when you want to chop wood?

Is it because an Ax is stronger and sharper, which makes it have more force on the wood?
I don't understand the question very well...

Answer 1

for #2.

the reason that a ax is more useful is because the pressure exerted is over a smaller area than with the hammer. The ax's blade is thin while the hammer's top is wider thus pressure is applied over a larger area so it's not as powerful.

example is when people can lay on a bed of nails. A person wouldn't be able to be on 1 nail since the pressure applied is much much greater. However when a person can lay on nails they lay on alot of nails together and thus the weight of the person is displaced over a large area. (force is reduced)