Why is detergent powder mixed with water to wash clothes?
Show Hint
Solution and Explanation
Detergents reduce the surface tension of water, allowing it to spread and wet clothes more effectively. They also form micelles that trap grease and dirt, allowing them to be rinsed away.
Top Questions on Surface tension
Define surface energy of the liquid. Obtain the relation between the surface energy and surface tension.
- MH Board Class XII - 2024
- Physics
- Surface tension
- A thin flat circular disc of radius 4.5 cm is placed gently over the surface of water. If surface tension of water is 0.07 Nm-1, then the excess force required to take it away from the surface is :
- NEET (UG) - 2024
- Physics
- Surface tension
- If \( M \) is the mass of water that rises in a capillary tube of radius \( r \), then the mass of water which will rise in a capillary tube of radius \( 2r \) is:
- MHT CET - 2024
- Physics
- Surface tension
- A big drop is formed by coalescing 1000 small droplets of water. The surface energy will become:
- MHT CET - 2024
- Physics
- Surface tension
- When two soap bubbles of radii \( a \) and \( b \) (\( b>a \)) coalesce, the radius of curvature of the common surface is:
- MHT CET - 2024
- Physics
- Surface tension
Questions Asked in MH Board Class XII exam
Derive an expression for energy stored in a charged capacitor. A spherical metal ball of radius 15 cm carries a charge of 2μC. Calculate the electric field at a distance of 20 cm from the center of the sphere.
- MH Board Class XII - 2024
- Capacitors
Draw a neat labelled diagram of Ferry's perfectly black body. Compare the rms speed of hydrogen molecules at 227°C with rms speed of oxygen molecules at 127°C. Given that molecular masses of hydrogen and oxygen are 2 and 32, respectively.
- MH Board Class XII - 2024
- The Kinetic Theory of Gases
Distinguish between an ammeter and a voltmeter. (Two points each).
The displacement of a particle performing simple harmonic motion is \( \frac{1}{3} \) of its amplitude. What fraction of total energy is its kinetic energy?
- MH Board Class XII - 2024
- Simple Harmonic Motion
Using the geometry of the double slit experiment, derive the expression for the fringe width of interference bands.
- MH Board Class XII - 2024
- Interference Of Light Waves And Young’S Experiment
An alternating voltage is given by \( e = 8 \sin(628.4 t) \).
Find:
(i) Peak value of e.m.f.
(ii) Frequency of e.m.f.
(iii) Instantaneous value of e.m.f. at time \( t = 10 \, {ms} \)- MH Board Class XII - 2024
- AC Voltage