Answer:
9.23 m/s
Explanation:
Let, the initial velocity be ux.
The horizontal velocity remans the same. So, time required, t = 25/ux
For vertical component, we know,
h = uy*t + (1/2)*g*t^2 [ g is positive because ball is falling downward ]
Putting in the values, we get,
36 = 0*(25/ux) + 1/2 * 9.81 * (25/u)^2
36 = 3065.625/u^2
u^2 = 85.15625
u = 9.23
[ If there's a problem with the solution, please inform me ]
The minimum speed with which Captain Brady had to run off the edge of the cliff to make it safely to the far side of the river is around 6 meters per second.
<h3>Further explanation</h3>
This is a free fall 2-dimensional type of problem, therefor we can write equations for both dimensions which model the fall of captain Brady. Let's call <em>x </em>the distance travelled by the captain on the horizontal direction and <em>y </em>the distance travelled on the vertical direction.
Lets suppose that Brady jumped with a complete horizontal velocity from a point which we will call the origin (meaning zero horizontal and vertical displacement), and let's call <em>ta</em> the time it took for captain Brady to reach the river (meaning the time he spent on the air). The equations of motion for the captain will be:


We know that at time <em>ta</em> the captain would have traveled 6.7 m on the horizontal direction, and 6.1 m in the vertical direction. Therefor we can write that:


Which gives us a system of 2 equations and 2 unknowns (<em>V</em> and <em>ta</em>). From the second equation we can solve for <em>ta</em> as:

And solving for <em>V</em> on the first equation, we find that:

Which is almost 6 meters per second.
<h3>Learn more</h3>
<h3>Keywords</h3>
Free fall, projectile, gravity
Physics is a natural science that involves the study of matter and its motion through space and time, along with related concepts such as energy and force.
Matter is generally considered to be anything that has mass and volume.
Scientific laws and theories express the general truths of nature and the body of knowledge they encompass. These laws of nature are rules that all natural processes appear to follow.
Distance = velocity (or speed) x time
so, distance = 0.30 meters.min x 15 mins
distance = 4.5 meters