A stone is thrown horizontally with an initial speed of 10 m/s from the edge of a cliff. A stop watch measures the stone's trajectory time from the top of the cliff to the bottom to be 4.3 s. What is the height of the cliff?

91 meter

To find the height of the cliff, you can use the formula for the vertical motion of an object in free fall:

h = (1/2) * g * t^2

where:
h is the height of the cliff
g is the acceleration due to gravity (approximately 9.8 m/s^2)
t is the time it takes for the stone to reach the bottom

In this case, the stone is thrown horizontally, which means its initial vertical velocity is zero. Therefore, the time it takes for the stone to reach the bottom is the same as the time it takes for it to fall vertically. In this case, the time is given as 4.3 seconds.

Plugging in the values into the formula:

h = (1/2) * 9.8 m/s^2 * (4.3 s)^2

h = 0.5 * 9.8 m/s^2 * 18.49 s^2

h = 90.107 m

So, the height of the cliff is approximately 90.107 meters.

In the vertical direction:

hf=hi+gt
0=hi-9.8t solve for hi

58meters