Answer:
The standard acceleration due to gravity (or standard acceleration of free fall), sometimes abbreviated as standard gravity, usually denoted by ɡ0 or ɡn, is the nominal gravitational acceleration of an object in a vacuum near the surface of the Earth. It is defined by standard as 9.80665 m/s2 (about 32.17405 ft/s2).
Explanation:
(Hint: the time<span> to rise to the </span>peak<span>is one-half the </span>total hang-time<span>.).</span>
<span>Your equation for the height of the stone at any time is h(t) = -16t2<span> + 128t + 32 .
From your equation, we can tell that you're defining the upward direction as
positive. We can also tell that you threw the stone upward, with an initial speed
as it left your hand of 128 feet per second, about 87 miles per hour ... a mighty toss indeed, and I think there's a man from the Chicago Cubs waiting outside
who'd like to talk to you.
Anyway, When the stone splashes into the water, h(t) = 0 .
</span></span>
<span>-16t²<span> + 128t + 32 = 0</span></span>
Divide each side by -16 :
t² - 8t - 2 = 0
I don't see any easy way to factor the expression on the left,
so I have to use the quadratic formula to solve this equation.
t = 4 plus and minus √18 .
t = +8.24 seconds
t = -0.24 second
Mathematically, both numbers are valid solutions.But when you apply
the equation to a real world situation, only the positive 't' makes sense.
So <u> t = 8.24 seconds</u>.
Sound needs a medium to propagate through and this medium which is moves through is the air. The colder the temperature is, the less excited (meaning kinetic energy) the air particles will be meaning that the sound wave will travel slower. In the sahara desert, since the temperatures are warmer, and more excited, the sound will propagate faster through the air.
*Note that sound waves rely on vibration to move and if the air is hotter the molecules in the air are vibrate more than compared to lower temperatures.