physics
posted by ashley .
A solid disc with radius R is is spinning. An object exerts a force F at the edge of the disc to slow down the disc. The disc slows down to rest in 2.0 seconds. How long would the disc take to stop if:
the mass of the disc doubled in s
the radius of the disc doubled in s
the force doubled in s

F=ma, so:
the mass of the disc doubled in s  it would take twice as long to stop
the radius of the disc doubled in s  it would take twice as long to stop
the force doubled in s  it would take half the time to stop 
55