a 100 kg car enters a level curve at 20m/s. if the curve has a radius of 80 m, what centripetal force must be applied by friction to keep the car from skidding?

the force on the thing and the distance the force moves the thing

iron would move it is magnetic there is a mag field around the current in the wire

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.

3. dark matter

empty space could also be a simple vacuum