InterviewSolution
Saved Bookmarks
| 1. |
21. A car starts with velocity 10 m's and scalerates at rate 5 m/s? Find the finalvelocity when the car has travelled a distar ca 30 m |
|
Answer» Using relation Vf - Vi = atVf - 10 = 5 * tt = (Vf - 10)/5 Now,S = Vi*t + 1/2 at^230 = 10*(Vf - 10)/5 + 1/2*5*[(Vf-10)/5]^2 30 = 2Vf - 20 + 5/2 *(Vf - 10)^2/25 30 = 2Vf - 20 + 5/2(Vf^2 + 100 - 20Vf)/25 30 = 2Vf - 20 + 1/10(Vf^2 + 100 - 20Vf) 50*10 = 20Vf + Vf^2 + 100 - 20Vf Vf^2 = 500 - 100 = 400 Vf = 20 Therefore,Final Velocity = 20 m/s |
|