Question

A body starts with initial velocity ‘u’ and moves with uniform acceleration ‘a’. If when the
velocity increased to 5u. The acceleration is reversed in direction, the magnitude remains
constant it turns to the starting point with velocity of ?
Explain.

Answer 1

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.