Advertisements
Advertisements
Question
Why does a helium balloon float in air?
Advertisements
Solution
Helium is much less denser than ordinary air which gives them buoyancy and thus float in air.
APPEARS IN
RELATED QUESTIONS
State the principle of floatation.
When a piece of wood is suspended from the hook of a spring balance, it reads 70 gf. The wood is now lowered into water. What reading do you expect on the scale of spring balance?
Why is the floating ice less submerged in brine than in water?
A piece of ice floating in a glass of water melts, but the level of water in the glass does not change.
Give reasons.
Hint: Ice contracts on melting.
A hollow metal cylinder of length 10 cm floats in alcohol of density 0.80 g cm-3, with 1 cm of its length above it. What length of cylinder will be above copper sulphate solution of density 1.25 g cm-3?
A test tube loaded with lead shots weighs 25 gf and floats upto the mark X in water. When the test tube is made to float in brine solution, it needs 5 gf more of lead shots to float upto level X. Find the relative density of brine solution.
A cube of ice whose side is 4.0 cm is allowed to melt. The volume of water formed is found to be 58.24 cm3. Find the density of ice.
Explain the following:
An egg sinks in fresh water but floats in a strong solution of salt.
Explain the following:
Icebergs floating in the sea are very dangerous for ships.
Why do petroleum-based products float on the surface of the water?
