a block of mass m 5.00 kg is
pulled along a horizontal frictionless floor by a cord
that exerts a force of magnitude F 12.0 N at an angle
u 25.0°. (a) What is the magnitude of the
block’s acceleration? (b) The force magnitude F is
slowly increased. What is its value just before the
block is lifted (completely) off the floor? (c) What is
the magnitude of the block’s acceleration just before
it is lifted (completely) off the floor?