Kinematics, multiple parts!! After a large earthquake, an airdrop of emergency s

Question

Kinematics, multiple parts!!

After a large earthquake, an airdrop of emergency supplies is arranged to the citizens of a small college town. Parachutes are in short supply, though, so the airdrop will rely on dropping the package precisely on a 10 m high pile of pillows stacked in the plaza. The aircraft is flying level at 300 m above flat ground at 70 m/s. Neglect the effects of air resistance (even though in practice this means airplanes don't work). How far from the pillows will the airplane have to drop the supplies? (Ground distance only, not the diagonal distance.) The pilot can aim this drop by measuring the angle between horizontal and the top of the pile. When he drops the supplies, what should this angle be? (It is drawn as theta in Fig. 2) The people of the town know that the supplies consist of full aluminum cans which, when dropped on 10 m high piles of pillows, can only survive impact speeds of less than 100.0 m/s. Will the cans survive or will the citizens go thirsty?

Explanation / Answer

Here ,

a)

height , h = 300 - 10

h = 290 m

a)

time taken by parachute to fall on ground ,

t = sqrt(2 * 290/9.8)

t = 7.7 s

distance , d = 7.7 * 70

d = 538.5 m

the distance is 538.4 m

b)

theta = arctan(290/538.4)

theta = 28.3 degree

the angle should be 28.3 degree

c)

let the speed of fall is v

v^2 - 70^2 = 2 * 9.8 * 290

v = 102.3 m/s

the speed of impact is more than 100 m/s

No , the cans will not survive

Related Questions

Navigate

• Browse (All)
• Browse K
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.