Indeed because some leave headlights off and ignore that fact since there are street lights around.
Wave speed = (wavelength) x (frequency)
= (1.5 m) x (500 / sec)
= 750 m/s .
Y₀ = initial position of the balloon at the top of the building = 44 m
Y = final position of the balloon at halfway down the building = 44/2 = 22 m
a = acceleration of the balloon = - 9.8 m/s²
v₀ = initial velocity of the balloon = 0 m/s
v = final velocity of the balloon = ?
using the kinematics equation
v² = v₀² + 2 a (Y - Y₀)
inserting the values
v² = 0² + 2 (- 9.8) (22 - 44)
v = 20.78 m/s
