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प्रश्न
Explain the following statement:
It is easier to cut with a sharp knife than with a blunt one.
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उत्तर
It is easier to cut with a sharp knife because even a small thrust causes great pressure at the edges and cutting can be done with less effort.
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संबंधित प्रश्न
Name the scientist who gave he magnitude of buoyant force acting on a solid object immersed in a liquid.
Relative density of a substance is expressed in g cm-3.
Explain why an iron needle sinks in water, but a ship made of iron floats on water.
How does the pressure exerted by thrust depend on the area of surface on which it acts? Explain with a suitable example.
Deduce an expression for the pressure at depth inside a liquid.
Pressure at the free surface of a water lake is P1, while at a point at depth h below its free surface is P2. (a) How are P1 and P2 related? (b)Which is more P1 or P2?
Two spheres A and B, each of volume 100 cm3 is placed on water (density = 1.0 g cm−3). The sphere A is made of wood of density 0.3 g cm−3 and sphere B is made of iron of density 8.9 g cm−3.
- Find:
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- The upthrust on each sphere.
- Which sphere will float? Give reason.
A body of mass 3.5 kg displaces 1000 cm3 of water when fully immersed inside it. Calculate:
- the volume of body,
- the upthrust on body and
- the apparent weight of body in water.
Figure shows the same block of wood floating in three different liquids A, B and C of densities ρ1, ρ2 and ρ3 respectively. Which of the liquid has the highest density? Give a reason for your answer.
The base of the cylindrical vessel measures 300 cm2. Water is poured into it up to a depth of 6 cm. Calculate the pressure of water on the base in the vessel.
