A package is dropped from a helicopter moving upward at 15m/s. If the helicopter was 1000m above the ground when the package was released, how long does it take before the package strikes the ground

yi = Initial height of the helicopter

yf = final height of the helicopter

vyi = component of the initial vertical velocity of the helicopter

g = gravity constant (9.8m/s^2)

yf = yi + vyideltat - 1/2gt^2

0m = 1000m + (15m/2)deltat - 1/2(9.8m/s^2)t^2

-1000m = (15m/s)t - (-4.9m/s^2)t^2

Use the quadratic formula

4.8t^2 - 15t - 1000 = 0

t1 = 15.75s and t2 = -12.65

t2 is rejected, time can't be negative

Thus, it takes 15.75s before the package strikes the ground.

the working equation for the angular size is the product of the physical size and 360 degrees divided by the product of two pi and distance from earth. the minimum size would be 0.559 degrees while the maximum size would be 0.49 degrees.