Answer:
Without this slack, a locomotive might simply sit still and spin its wheels. The loose coupling enables a longer time for the entire train to gain momentum, requiring less force of the locomotive wheels against the track. In this way, the overall required impulse is broken into a series of smaller impulses. (This loose coupling can be very important for braking as well).
Explanation:
1h----------------> 70x3=210 bacteria
2h-----------------> 210*3=630 bactaeria
let be y the number of bacteria at the t=0h
it is y=70 3^0
for t= 1h
y=70*3^1=210
for t=2h
y=70*3^2=630
so we can write y=70*3^x, where x is the number of hour
Answer:
The hunter should aim directly at the perched monkey because the tranquilizer dart will fall away from the line sight at the same rate that the monkey falls from its perch.
Tan theta = 9 / 90 = .1 so theta = 5.71 deg
The time for the monkey to reach the ground is
t = (2 h / g)^1/2 = (18 / 9.8)^1/2 = 1.36 sec
So the horizontal speed of the dart must be at least
Vx = 90 m / 1.36 sec = 66.4 m/s
Vx = V cos theta
V = 66.4 m/s / cos 5.71 = 66.7 m/s
K.E1=1/2×100×3²
=50×9
=450J
K.E2=1/2×100×36
=50×36
=1800J