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प्रश्न
Explain the following:
A hydrometer is made heavy near the bottom.
उत्तर
The bottom of the hydrometer is made heavier by loading it with lead shots so that it floats vertically with some of its portion outside the surface of the water in the jar.
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संबंधित प्रश्न
Draw a diagram to show the forces acting on a body floating in water with its some part submerged. Name the forces and show their points of application. How is the weight of water displaced by the floating body related to the weight of the body itself?
A block of wood is so loaded that it just floats in water at room temperature. What change will occur in the state of floatation, if
(a) Some salt is added to water, (b) Water is heated?
Give reasons.
A body of volume V and density ρs , floats with volume v inside a liquid of density ρL. Show that `"v"/V = ρ_s/ρ_L` .
An iron nail sinks in the water while an iron ship floats on water. Explain the reason.
A body floats in a liquid A of density ρ1 with a part of it submerged inside the liquid, while in liquid B of density ρ2 it is totally submerged inside the liquid. The densities ρ1 and ρ2 are related as :
What fraction of metal of density 3400 kgm-3 will be above the surface of mercury of density 13600 kgm-3, while floating in mercury?
A test tube loaded with lead shots, weighs 150 gf and floats upto the mark X in water. The test tube is then made to float in alcohol. It is found that 27 gf of lead shots have to be removed, so as to float it to level X. Find R.D. of alcohol.
A block of wood of volume 25 cm3 floats in water with 20 cm3 of its volume immersed in water.
Calculate:
(1) density of wood
(2) the weight of block of wood.
Assertion: To float, body must displace liquid whose weight is equal to the actual weight.
Reason: The body will experience no net downward force in that case.
Assertion (A): Lactometer is used to check the purity of milk.
Reason (R): Lactometer measures the cream content of milk.