Newton's law of motion?

While sitting on a tree branch 10.0 m above the ground, you drop a chestnut. When the chestnut has fallen 2.0 m, you throw a second chestnut straight down. What initial speed must you give the second chestnut if they are both to reach the ground at the same time?

m/s

Newton's law of motion?
The first chestnut falls 10.0 m but falls only 8.0 m counting from the time the second chestnut is thrown. Thus (1/2) g T^2 = 8 m defines the time the first chestnut reaches the ground. T = SQRT ( 16 m / g ) = 4 SQRT (1/g)



The second chestnut falls 10 m = V T + (1/2)g T^2 = V T + 8;

V = 2/T = (1/ 2) SQRT (g) = 1.56m/s if g= 9.8 m/s^2