BITSAT 2018
- Exam
- BITSAT
- Year
- 2018
- Subject
- Physics
- Chapter
- Mechanical Properties of Fluids
BITSAT 2018 · Physics · Mechanical Properties of Fluids
If a drop of liquid breaks into smaller droplets, it results in...
If a drop of liquid breaks into smaller droplets, it results in lowering of temperature of the droplets. Let a drop of radius , break into small droplets each of radius , then decrease (drop) in temperature (given, specific heat of liquid drop and surface tension )
Options
- A
- B
- C
- D
Correct answer
D.
Step-by-step solution
since, volume remains unchanged, during this phenomenon, so
Now, change in surface area
Energy released = T \
Here, all this energy released is al the \cos t of lowering the temperature and mass of the big drop of liquid ρ</p><p>Now, change in temperature, \Delta\theta = \dfrac{\Delta U}{ms}</p><p>=\dfrac{T \times 4\pi\left(R^{2} - Nr^{2}\right)}{ \left(\dfrac{4}{3}\piR^{3}ρ\right)S}
= \dfrac{3T}{ρS} \left(\dfrac{1}{R} - \dfrac{1}{r}\right)$