Related questions with answers

The number of accidents that occur at a busy intersection is Poisson distributed with a mean of 3.5 per week. Find the probability of the following events: Five or more accidents in one week

When a normal elevator starts going up, you feel a jerk until it gets up to speed) This is because the acceleration changes almost instantly from zero to some positive value) In this problem you will explore another way for an elevator's acceleration to be arranged such that the jerk is minimized)

a) Suppose an elevator starts from rest (v=0) at the bottom floor (s=0 ft) and is given a constant acceleration of 2 $(ft / {sec}^2)$ for 6 sec. Thereafter, the elevator rises with constant velocity. Find the velocity and displacement of the elevator as functions of time) Sketch three graphs: acceleration, velocity, displacement, for times t=0 to t=10 sec

b) How does the acceleration graph show that passengers on the elevator get a jerk at t=0 and another jerk at t=6 ?

c) If the acceleration increases gradually to a maximum value, then decreases gradually to zero, the jerks will be eliminated) Show that if the acceleration is given by

a=2-2 \cos (\pi / 3) t

for the first 6 sec, then the elevator's acceleration has this property.

d) Using the acceleration function in part c, find the velocity as a function of time)

e) Sketch the graph of velocity as a function of time, if the velocity remains at its value at t=6 seconds as the elevator goes up. How does this velocity graph differ from that in part a?

f) How far does the elevator go while it is getting up to top speed?

g) The elevator is to be slowed down the same way it was speeded up, over a 6 second time period) If the elevator is to go all the way to the 50 th story, 600 ft above the bottom floor, where should it start slowing down?

h) How long does it take for the elevator to make the complete trip?

i) If the elevator were to go up just one floor 12 ft, would the new acceleration and deceleration functions in part c and f still provide a smooth ride? If so, how do you tell? If not, what functions could be used to smooth out the ride?

If a monopolist is producing a level of output where MR is less than MC, then it should

a. Shift its marginal cost curve upward.
b. Increase its output.
c. Lower its output.
d. Lower its price.

Question

Why would a farmer want to know about the soil on his or her farm?

Solution

Verified

The farmer needs to have all the information he could possibly gather about the soil he wants to use for his plants. The reason for this is quite simple - he needs to know whether the condition and the quality of the soil are appropriate for those plants he intends to sow.