Home
Class 11
PHYSICS
A needle floats in clean water, but sink...

A needle floats in clean water, but sinks in soap solution. Why?

Text Solution

Verified by Experts

The surface tension of water being large as compared to soap solution. When the surface tension is high, the upper surface of water acts as stretched membrane. It can support the weight of the needle. So, a needle floats in clean water.
Promotional Banner

Topper's Solved these Questions

  • PROPERTIES OF MATTER

    PREMIERS PUBLISHERS|Exercise OTHER IMPORTANT QUESTION & ANSWERS (NUMERICAL PROBLEMS)|56 Videos

  • PROPERTIES OF MATTER

    PREMIERS PUBLISHERS|Exercise OTHER IMPORTANT QUESTION & ANSWERS (LONG ANSWER QUESTIONS)|20 Videos

  • OSCILLATIONS

    PREMIERS PUBLISHERS|Exercise OTHER IMPORTANT QUESTIONS & ANSWERS ( CONCEPTUAL QUESTIONS.)|24 Videos

  • QUESTION PAPER MARCH 2019

    PREMIERS PUBLISHERS|Exercise Part- IV|23 Videos

Similar Questions

Explore conceptually related problems

Why does an iron needle sink in water, but not an iron ship?

A boat carrying a few number of big stones floats in a water tank. If the stones are unloaded into water, the water level:

Air is pushed into a soap bubble of radius r to double its radius, of the surface tension of the soap solution is S, the work done in process is

A body floats in water with 40% of its volume outside water. When the same body floats in oil 60% of its volume remains outside oil. What is the relative density of the oil ?

Do all objects that sink in water, sink in oil ? Give reason.

A wire forming a loop is dipped into soap solution and taken out so that a film of soap solution is formed. A loop of 6.28 cm long thread is gently put on the film and the film is pricked with a needle inside the loop. The thread loop takes the shape of a circle. Find the tension in the thread. Surface tension of soap solution =0.030Nm^-1 .

Why is it easier for you to float in salt water than in fresh water?

PREMIERS PUBLISHERS-PROPERTIES OF MATTER-OTHER IMPORTANT QUESTION & ANSWERS (CONCEPTUAL QUESTIONS)
  1. Why a small bubble rises slowly through a liquid whereas the bigger bu...

    Text Solution

    |

  2. Mercury does not wet the glass. Why?

    Text Solution

    |

  3. A needle floats in clean water, but sinks in soap solution. Why?

    Text Solution

    |

  4. A piece of chalk when immersed in water emits bubbles. Why?

    Text Solution

    |

  5. Small bits of camphor dance about in clear water but not on one contam...

    Text Solution

    |

  6. Oil calms the stormy waves on the sea. Why?

    Text Solution

    |

  7. Explain why sand is drier than clay.

    Text Solution

    |

  8. Two streamlines cannot cross each other. Why ?

    Text Solution

    |

  9. Why is the tip of the nib of a pen split?

    Text Solution

    |

  10. Why tiny drops of fog act as rigid bodies?

    Text Solution

    |

  11. Small drops of mercury are found to assume a spherical shape. Why?

    Text Solution

    |

  12. Why does a stone sink when placed on the surface of water?

    Text Solution

    |

  13. Among solids, liquids and gases, which can have all the three modulus ...

    Text Solution

    |

  14. Write copper, steel, glass and rubber in the order of increasing coeff...

    Text Solution

    |

  15. Which is more elastic -water or air?

    Text Solution

    |

  16. Why are springs made of steel & not of copper ?

    Text Solution

    |

  17. Following are the graphs of elastic materials which one corresponds to...

    Text Solution

    |

  18. It is difficult to stop bleeding from a cut in human body at high alt...

    Text Solution

    |

  19. In soldering, addition of flux makes soldering easily why?

    Text Solution

    |

  20. Which type of strain is there, when a spiral spring is stretched by a ...

    Text Solution

    |