Question

A force of 90 Newtons is applied to a 20 cm2 surface.

The force applied is then increased by 5 Newton’s and the surface area is increased by 5 cm^2

Answer 1

The given question is incomplete. The complete question is:

A force of 90 Newton's is applied to a
`20cm^2` surface. The force applied is then increased by 5 Newton's and the surface is increased by
`5cm^2`. What percentage does the outcome decrease by

Answer: The outcome decreases by 15.5 %

Explanation:

Pressure is defined as the ratio of force per unit area.

`Pressure=(Force)/(Area)`

Case 1:
`P_1=(90N)/(20cm^2)=4.5Ncm^(-2)`

Case 2:
`P_2=(95N)/(25cm^2)=3.8Ncm^(-2)`

Decrease in pressure =
`P_1-P_2` =
`(4.5-3.8) Ncm^(-2)=0.7Ncm^(-2)`

Percentage decrease =
`(0.7)/(4.5)* 100\%=15.5\%`

Thus the outcome decreases by 15.5 %