posted by Vince on .
Why does a rubbed balloon stick to the wall?
The rubber ballon acquires a negative charge when rubbed. (I takes electrons away from the rubbing material).
The negative charge of the ballon induces a positive charge on the ceiling surface, even if there is zero electrical conductivity there. The induced charge can be due to surface polarization. If the ceiing has small nonzero conductivity but is not grounded, some ceiling electrons will be repelled by the ballon. Either way, an attraction force will exist between ceiing and balloon.
wrench falls out of the gondola of a balloon
that is 540 m above the ocean.
Assuming negligible air resistance, what
was the wrench’s speed as it hit the water?
The acceleration of gravity is 9.8 m/s
Answer in units of m/s