6the speed of a ball suspended by a rope of length 0.5 m, rotating one revolution each 2 seconds is: (S=2.pi. r/T)

0.55 m/s

0.82 m/s

1 m/s

1.57 m/s

20) what is a magnetic field? 21) in which direction do magnetic field lines always point? 22) sketch a diagram showing how a plotting compass points around a 23) name two magnetic poles that will: a) attract each other b) repel each other. 24) explain why you can use a compass to navigate. 25) what's an electromagnet? 26) list two ways to increase the strength of an electromagnet. 27) the wire in a simple motor feels a force when a current flows through it. why is this? i need answers to check mine