mdforce work-done

Question

3.2. a bike with mass of 750kg is travelling at 33m/s on a horizontal road. Calculate the retarding force required to stop the bike in 110m. 3.3. a motorcar with a mass of 580kg accelerates uniformly from rest down an incline 8 degrees with the horizontal to velocity of 16m/s over a distance of 115m. the resistance against motion is 340N. Calculate the ffg: 3.3.1. the travel force required to move the car down the slope 3.3.2. the work done by the tractive force

Answer 1

3.2) 

Mass of the bike, m = 750 kg

Initial speed of the bike , u = 33 m/s

distance , d = 110 m

Final speed, v = 0

Find the retarding force by using work - energy principal.

T1 + U1-2 = T2

(1/2)mu² - Fd  = (1/2)mv²

(1/2)(750)(33)² - F(110)  = (1/2)(750)(0)²

110F = 408375

F = 3712.5 N