Question

If pressure at half the depth of a lake is equal to 2/3 the
pressure at the bottom of the lake then what is the
depth of the lake

(a) 10 m
(b) 20 m
(C) 60 m
(d) 30 m​

Answer 1

Answer:(b)

Explanation:

Pressure at bottom of the lake =P0+hρg and pressure at half the depth of a lake =P0+h2ρg  

According to given condition  

P0+12hρg=23(P0+hρg)⇒13P0=16hρg  

⇒h=2P0ρg=2×105103×10=20m.