Question

A 2.29N force is applied to the plunger of a hypodermicneedle.

Answer 1

Answer:

0.04651 N

Explanation:

$F_1$ = Force on plunger = 2.29 N

$d_1$ = Diameter of plunger = 1.27 cm

$d_2$ = Diameter of needle = 0.181 cm

$F_2$  = Force on needle

From Pascal's law we have

$\dfrac{F_1}{A_1}=\dfrac{F_2}{A_2}\\\Rightarrow F_2=\dfrac{F_1\times A_2}{A_1}\\\Rightarrow F_2=\dfrac{2.29\times \pi\dfrac{0.181^2}{4}}{\dfrac{\pi 1.27^2}{4}}\\\Rightarrow F_2=0.04651\ N$

The force with which the fluid leaves the needle is 0.04651 N