Question

plz help me with hw A bus of mass 1000 kg moving with a speed of 90km/hr stops after 6 sec by applying brakes then calculate the distance travelled and amount of force applied.​

Answer 1

Mass, M = 1000 kg

Speed, v = 90 km/h = 25 m/s

time, t = 6 sec.

Distance:

`{ \tt{distance = speed * time }} \\ { \tt{distance = 25 * 6}} \\ { \tt{distance = 150 \: m}}`

Force:

`{ \tt{force = mass * acceleration}} \\ { \bf{but \: for \: acceleration : }} \\ from \: second \: equation \: of \: motion : \\ { \bf{s = ut + (1)/(2) {at}^(2) }} \\ \\ { \tt{150 = (0 * 6) + ( (1)/(2) * a * {6}^(2) ) }} \\ \\ { \tt{acceleration = 8.33 \: {ms}^( - 2) }} \\ \\ { \tt{force = 1000 * 8.33}} \\ { \tt{force = 8333.3 \: newtons}}`