a uniform cylinder of radius r and mass m rests on a horizontal plank. the plank slides horizontally with acceleration a. if the cylinder rolls without slipping, what is its acceleration relative to the plank and the ground?

Density of salty water as compared to the density of pure water is(a) is less(b) is always equal(c) is always more(d) may be less or more

Which is an example of gaining a static charge by conduction? a) rubbing a balloon against your hair. b) shuffling your shoes across a carpet. c) bringing a charged rod near an electroscope. d) touching your car on a cold day and getting a shock.

It is really hard for me right know