A hot-air balloon is rising upward with a constant speed of 4.00 m/s. When the balloon is 4.77 m above the ground, the balloonist accidentally drops a compass over the side of the balloon. How much time elapses before the compass hits the ground?

u=4m/s

when constant speed, acceleration a=0
distance s=4.77
time t=?
s=u*t+1/2*a*t^2
s=u*t because a=0
t=s/u=4.77/4
t=1.77 sec.

To determine how much time elapses before the compass hits the ground, we can use the equation of motion for vertical motion with constant acceleration. Since we are dealing with a uniform upward velocity, the acceleration is zero. The equation of motion in this case is:

h = ut + (1/2)gt^2

Where:
h = height (4.77 m)
u = initial velocity (0 m/s, as the compass is dropped)
g = acceleration due to gravity (-9.8 m/s^2, taking the direction into account)
t = time

Given that the initial velocity (u) is zero, the equation simplifies to:

h = (1/2)gt^2

Rearranging the equation to solve for time (t):

t^2 = (2h) / g
t = sqrt((2h) / g)

Substituting the given values into the equation:

t = sqrt((2 * 4.77) / 9.8)

Simplifying the expression:

t = sqrt(0.4887)

Calculating the square root:

t ā‰ˆ 0.7 seconds

Therefore, the compass will hit the ground approximately 0.7 seconds after it is dropped from the balloon.