Question

С балкона высотой 15м бросили вертикально вверх мяч с начальной скоростью 10м/с. Найти в СИ время, через которое мяч упадёт на землю. Ускорение свободного падения принять равным 10м/с^2. (3c)

Answer 1

Дано:
h=15 м
v0=10 м/с
g=10 м/с²
---------------------
t-?
Решение:
-V0t=h-gt²/2
-10t=15-5t²
5t²-10t-15=0
t²-2t-3=0
D=b²-4ac=2²+4*3*1=16
t1=(2+4)/2=3
t2=(2-4)/2=-2

Ответ: 3с.

Answer 2

Calculation of Time for the Ball to Fall to the Ground

To calculate the time it takes for the ball to fall to the ground, we can use the equation for the height of an object in free fall:

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

Where: - h is the initial height of the ball (15m) - u is the initial velocity of the ball (10m/s) - g is the acceleration due to gravity (10m/s^2) - t is the time it takes for the ball to fall to the ground (unknown)

We can rearrange the equation to solve for t:

t = sqrt((2h)/g)

Substituting the given values:

t = sqrt((2 * 15) / 10) = sqrt(3) ≈ 1.73 seconds

Therefore, the ball will take approximately 1.73 seconds to fall to the ground.