Answer:
Explanation:
Given
height of grand canyon is 
Rock is dropped i.e. initial velocity is zero

Using Equation of motion

h=height
u=initial velocity
a=acceleration
t=time
here a=acceleration due to gravity


False its an unbroken loop that allows electrons to flow through constantly
I actually know the answer to this one, you use pennies to find the atomic weight of a penny, it really doesn't have a weight. LOL
Let <em>F</em> be the magnitude of the force applied to the cart, <em>m</em> the mass of the cart, and <em>a</em> the acceleration it undergoes. After time <em>t</em>, the cart accelerates from rest <em>v</em>₀ = 0 to a final velocity <em>v</em>. By Newton's second law, the first push applies an acceleration of
<em>F</em> = <em>m a</em> → <em>a</em> = <em>F </em>/ <em>m</em>
so that the cart's final speed is
<em>v</em> = <em>v</em>₀ + <em>a</em> <em>t</em>
<em>v</em> = (<em>F</em> / <em>m</em>) <em>t</em>
<em />
If we force is halved, so is the accleration:
<em>a</em> = <em>F</em> / <em>m</em> → <em>a</em>/2 = <em>F</em> / (2<em>m</em>)
So, in order to get the cart up to the same speed <em>v</em> as before, you need to double the time interval <em>t</em> to 2<em>t</em>, since that would give
(<em>F</em> / (2<em>m</em>)) (2<em>t</em>) = (<em>F</em> / <em>m</em>) <em>t</em> = <em>v</em>
Explanation:
You are given the initial velocity, the displacement, and the acceleration. You're looking for the final velocity. So you use the equation:
v² = v₀² + 2aΔy
When you solve for v, you take the square root. Your calculator will return a positive answer, but there are actually two possible answers: positive and negative.
v = ±√(v₀² + 2aΔy)
You must use the physical context of the problem. If we take up to be the positive direction, then v must be negative, since the projectile is moving down.