A 2-kg mass placed 30-cm to the left of the fulcrum is balanced by
a 1-kg mass placed cm to
the right of the fulcrum.

4. who was the first one to measure the speed of light and conclude that it is finite? 5. who was the first philosopher who thought the speed of light is finite? 13. what is the speed of light numerically? 14. give an example of something moving faster than light 15. give an example for some particles or waves that

The boy of mass 30 kg is at r1= 2 meters from the fulcrum. of the girl is 45 kg, at what r2 must she sit so that they are balanced ?

What is friction? how does it affect the motion of an object?