A test tube of radius 1.0cm is loaded to 8.8g. If is placed upright in water; find the depth to which it would sink

A. 2.8cm
B. 5.2cm
C. 25.5cm
D. 28.0cm

Correct Answer:

Option A = 2.8cm

Explanation

Pressure = ^F/_A = pgh, where p = density, h = depth and g = 10ms^-2
But F = P x A
∴ Force exerted by the load test tube = cross-sectional Area x Pressure
i.e F = A x pgh

∴ h =	F_
	A x pg

 

=	mg
	A x P x g

 

=	8.8 x 10-3 x 10
	πr2 x p x g

 

=	_8.8 x 10-3 x 10
	π x (1.0-2)2 x 1000 x 10

= 0.028m or 2.8m