The pilot of an airplane traveling 240 km/h wants to drop supplies to flood victims isolated on a patch of land 160 m below. The supplies should be dropped how many seconds before the plane is directly overhead?

What time does it take for an object to fall 160m?

160 = .5gt^2

= 5.7s

The cliff divers of Acapulco push off horizontally from rock platforms about 30.6 m above the water, but they must clear rocky outcrops at water level that extend out into the water 5.0 m from the base of the cliff directly under their launch point. See the figure. What minimum pushoff speed is necessary to clear the rocks? (m/s)

To determine how many seconds before the plane is directly overhead the supplies should be dropped, we need to calculate the time it takes for the supplies to fall from the plane to the ground.

First, let's convert the speed of the airplane from km/h to m/s. Since 1 km equals 1000 m and 1 hour equals 3600 seconds, we can calculate the speed in m/s as follows:

240 km/h * (1000 m/km) / (3600 s/h) = 66.67 m/s (approximately)

Now, we can use the formula for calculating the time it takes for an object to fall vertically:

t = √(2h / g)

where:
t = time in seconds
h = height in meters
g = acceleration due to gravity, approximately 9.8 m/s²

Plugging in the given values:

t = √(2 * 160 m / 9.8 m/s²)
= √(320 m / 9.8 m/s²)
= √32.65 s²
≈ 5.71 s

Therefore, the supplies should be dropped approximately 5.71 seconds before the plane is directly overhead.