) Sam, whose mass is 75 kg, takes off on flat snow on his jet skis. The skis have a thrust of 197 N and a coefficient of kinetic friction in snow of 0.1. Unfortunately, the skis ran out of fuel after only 8 seconds.
Answer 1
(a).
a = (F – f_friction)/m
a = (F – µmg)/m
one = (197 – 0.1 * 75 * 9.8)/75
a = 1.647 m/s²
v=em=1647*8
v = 13.173 m/s
(B).
save energy
first stage condition;
Fs = ½ mV² + µmg
197s = ½ (75)(13.173)² + 0.1 (75)(9.8)s
solving for s, we get
s = 52.693m
second stage condition;
½ mV² + (-µmg S) = 0
½(75)(13.173)² + (-0.1 * 75 * 9.8S) = 0
solve for S,
S = 88.535m
total distance = s + S = 52.693 + 88.535 = 141.23 m