JEE Main2012PhysicsMechanical Properties of FluidsActual
A thin liquid film formed between a U-shaped wire and a light slider supports a weight of 1.5 10⁻² ~N (see figure). The length of the slider is 30 ~cm and its weight negligible. The surface tension of the liquid film is
Options
- A0.0125 ~Nm ⁻¹
- B0.1 ~Nm ⁻¹
- C0.05 ~Nm ⁻¹
- D0.025 ~Nm ⁻¹
Correct answer
D. 0.025 ~Nm ⁻¹
Step-by-step solution
The force of surface tension acting on the slider balances the force due to the weight. array ll & F =2 ~T = w & 2 ~T (0.3)=1.5 10⁻² & T =2.5 10⁻² ~N / m array