Question

A body starts from a point o with a velocity.v.and uniform acc alpha the direction.of acc is reversed

Answer 1

if direction of acceleration is reversed from positive X axis to negative X axis that means the body is performing retardation .

Answer 2

ANSWER

I. By III equation of motion,

v

2

=u

2

+2as

(5v)

2

=u

2

+2as

25v

2

−u

2

=2as

24u

2

=s

2a

∴ Distance travelled =S=

a

12u

2

II. v

2

=u

2

+2as

v

2

=(5u)

2

+2(−a)(

a

12v

2

)

v

2

=25v

2

−24u

2

v

2

=u

2

v=1u

⇒v=−u.