Question

Answer for the 15th question

Answer 1

Explanation:

given: u = 5m/sec, v = 0, t = 4 sec, a = ?

to find retarding force F

formula used: v = u + at

=> 0 = 5 + a × 4

=> 0 = 5 + 4a

=> 5 + 4a = 0

=> 4a = - 5

=> a = - 5/4 = - 1.25 m/sec²

therefore retarding force F = ma

=> 1000 × - 1.25

=> - 1250 N