QJEEAdv08Phee4a: JEE Advanced 2008 Physics - Class 11 JEEAdv08Phee4a Solution: STATEMENT - 1 : The stream of water flowing at high speed from…
STATEMENT - 1 :
The stream of water flowing at high speed from a garden hose pipe tends to spread line a fountain when held vertically up, but tends to narrow down when held vertically down.
and
STATEMENT - 2 :
In any steady flow of an incompressible fluid, the volume flow rate of the fluid remains constant.
Multiple Choice Options
- A Statement - 1 is True, Statement - 2 is True; Statement - 2 is a correct explanation for Statement - 1
- B Statement - 1 is True, Statement - 2 is True; Statement - 2 is NOT a correct explanation for Statement - 1
- C Statement - 1 is True, Statement - 2 is False
- D Statement - 1 is False, Statement - 2 is True
Step-by-Step Verified Solution
Volume flow rate (V) of an incompressible fluid in the steady flow remains constant.
Where = area of cross-section and = velocity
If ' ' decreases, ' ' increases and vice-versa.
When steam of water moves up, its speed (v) decreases and therefore 'a' increases, i.e., the water spreads out like a fountain. When steam of water from hose pipe moves down, its speed increases and as a result, area of cross-section decreases.
Therefore, statement - 1 is true.
Statement - 2 is the correct explanation of statement - 1.