Question

plz answer this on copy with easy explaination ​

Answer 1

Answer:

acceleration = 0.21 m/s²

retardation =  0.42 m/s²

Maximum Speed =  8.33 m/s

Explanation:

Let say acceleration = a  m/s²

Distance Covered in 40 sec Using S = ut + (1/2)at²

= 0 + (1/2)a40² = 800a

Then Velocity after 40 sec  using V = U + at

=  40a  m/s

Distance covered in 4 min = 240 sec  = 40a * 240

= 9600 a  m

Deceleration in 20 sec =  (0- 40a)/20 =  -2a

Distance covered in 20 sec  =  40a*20  + (1/2)(-2a)20²

= 800a - 400a

= 400a

Total Distance Covered = 800a + 9600a + 400a

= 10800 a

10800 a = 2250 m

=> a = 0.21 m/s²

acceleration = 0.21 m/s²

retardation = 2 * 0.21 = 0.42 m/s²

Maximum Speed = 40a = 8.33 m/s