Question

can speed of an object be nagetive? justify.

Answer 1

hi friend here is your answer

No, speed of a object cannot be negative. Speed is a restricted quantity in physics because it only tells how fast something is going; such quantities are called scalars. ... But if I say it is moving at 20 m/s West, that is its velocity (speed with direction).

Answer 2

Hey friend!!

No, the speed of an object couldn't be negative. 
As the speed is equal to distance by time (d= u/t). Speed being a scalar quantity has only magnitude(distance traveled cul'd be in any direction) which only tells about the distance traveled but not the direction. Thus its never negative. The speed is a restricted quantity in physics.

Hope it really helps....