posted by jojo .
Which three options are true about motion in a straight line.
A. A particle which moves at an increasing velocity has a constant acceleration.
B. If two particles always have the same velocity as each other, their separation does not change.
C. A particle which has zero acceleration moves with constant velocity or is stationary.
D. A particle with negative position must have had a negative acceleration in the past.
E. The acceleration of any subject is 9.8m s^-2
F. A particle which moves with a constant acceleration also has a constant velocity.
G. An object which is dropped and falls only under gravity accelerates downwards at approximately 9.8m s^-2
H. Velocity is the magnitude of the speed.
I think A, B and G. Can anyone help?