Question

Identical wire loops are dipped into Liquid X and Liquid Y, so that a film of liquid forms across the loops (like the bubble solution on a child's bubble blowing wand). The width of each loop is increased slowly and the forces FX and FY needed to make the loops 5% wider are measured.
a. FX will be greater than F Y
b. FX will be less than FY
c. FX will be equal to FY
d. It's impossible to predict whether F X or FY will be greater without more information.

Answer 1

Answer:

a.

Explanation:

Assuming that Liquid X is considered to possess a greater viscosity as well as higher surface tension than liquid Y. Then, liquid X will tend to harbour more pressure inside the liquid.

In addition to that, the greater the surface tension, the greater the force required to expand the liquid's surface area.

This in turn makes the force required to make the loop 5% wider to be greater in FX rather than FY.

Thus, option a is the correct answer.