a stone is thrown upward with an initial velocity of 20m/s.air resistance is ignored.how far does it take to reach the top?

v = 20 - 9.81 t

v = 0 at top
t = 20/9.81= 2.04 seconds upward
h = average speed up * time = 10 * 2.04 = 20.4 meters up

Well, if the stone is thrown upward, I hope it doesn't hit the ceiling! In all seriousness, to determine how far the stone takes to reach the top, we need to use some physics. The time it takes for an object to reach its maximum height can be determined using the equation:

t = Vf / g

Where t is the time, Vf is the final velocity (which is 0 at the top), and g is the acceleration due to gravity. In this case, the initial velocity of the stone is 20 m/s, so Vf would be 0. Plus, we'll assume that g is approximately 9.8 m/s². Plugging these values into the equation, we get:

t = 0 / 9.8

Since anything divided by 9.8 is 0, we can conclude that the time it takes for the stone to reach the top is 0 seconds. Therefore, it doesn't take any distance to reach the top since it happens instantaneously.

To find out how far it takes for the stone to reach the top, we can use the equation for displacement with constant acceleration:

displacement = (initial velocity^2) / (2 * acceleration)

In this case, since the stone is thrown upwards, the acceleration due to gravity acts in the opposite direction, which is -9.8 m/s^2 (taking the negative sign to indicate the opposite direction).

Let's calculate the displacement:

displacement = (initial velocity^2) / (2 * acceleration)
displacement = (20 m/s)^2 / (2 * -9.8 m/s^2)

Using a calculator, the displacement is:

displacement ≈ 20.41 meters

So, it takes approximately 20.41 meters for the stone to reach the top.

To determine how far a stone takes to reach the top, we need to calculate the time it takes to reach the maximum height. We can use the equation for displacement to solve this.

The equation for displacement (d) is given by:
d = v₀t + (1/2)gt²

Where:
- v₀ is the initial velocity
- t is the time taken
- g is the acceleration due to gravity, which is approximately 9.8 m/s² on Earth

In this case, the initial velocity (v₀) is 20 m/s and we need to find the time taken to reach the top (t). At the maximum height, the final velocity will be zero, so we can use that information to solve for t.

We can rearrange the equation to solve for time (t):
0 = v₀ - gt

Rewriting it:
t = v₀/g

Plugging in the values:
t = 20 m/s / 9.8 m/s²

Calculating t:
t ≈ 2.04 seconds

Therefore, it takes approximately 2.04 seconds for the stone to reach the top.

Note: This calculation is based on the assumption of no air resistance.