initial angular speed is given as 20 rev/second
so it is given as
now it comes to rest after 80 s
now we can use kinematics to find angular deceleration
so angular deceleration is 1.57 rad/s^2
It can be purified or be used by a filter
True. If the amount displaced is more than the mass, it floats. If the amount is less than the mass, it will sink.
Light bulbs, think about parallel circuits as something you plug into, so for example you plug in a tv for it to work, same with a refrigerator and Christmas lights
When we give energy to the electrons, or when electrons gain energy, it jumps into the outer orbital !