Class IXth physics questions

[Shrishti]

I wanted to know about the following:
1. Why does a Helium baloon only rise to a particular hieght and thereafter does not rise further?
2. Why do cricketers shoes have spikes in them?

Thank you

[hummer]

the pressure inside the helium baloon is less than the surrounding atmospheric pressure. Due to this the helium baloon starts going upward towards lower pressure.It will move till it reaches a place where the pressure inside the baloon became equal to the surrounding pressure. After that it will stop moving upward.

To create friction between the boot and the ground.So that the player do not slip while playing.

Are you satisfied if not then go to the related topic in some book.

[Binsi]

hey great work

[hummer]

8)

[Binsi]

i didnt eactly understand what you meant here