Ok so this is simple projectile motion problem.
if we have an object falling in free fall it is subject to gravity of -9.80m/s^2
so it says it takes 6 sec to fall and we know initial velocity was zero so we know that h=vt+1/2gt^2 so we get h=0+1/2*9.80*6^2 = 176.4m
so solving for final speed we get KE=PE = 1/2mv^2=mgh = 1/2v^2=gh so
v=sqrt(2*g*h) = sqrt(2*9.8*176.4m) = 58.8m/s final speed when it hits the ground
hope this helps you! Thanks!!
The relevant equation we can use in this problem is:
h = v0 t + 0.5 g t^2
where h is height, v0 is initial velocity, t is time, g is
gravity
Since it was stated that the rock was drop, so it was free
fall and v0 = 0, therefore:
h = 0 + 0.5 * 9.81 m/s^2 * (4.9 s)^2
<span>h = 117.77 m</span>
Answer:
V = 20 miles /sec
Explanation:
We have remaining distance = d = 96 miles
Lets call Pascal velocity V in miles per hour
Now if he increases his velocity by 50 % (equivalent to multiply by 1.5 ) he will need a time t₁ to arrive then as V = d/t
1.5* V = d/ t₁ ⇒ 1.5 * V = 96 /t₁
And in the case of reducing his velocity
(V / 4) = d/ (t₁ + 16 ) ⇒ V * (t₁ + 16 ) = 4*d ⇒ V*t₁ + 16*V = 384
So we a 2 equation system with two uknown variables
1.5*V = 96/t₁ (1)
V*t₁ + 16*V = 384 (2)
We solve from equation (1) t₁ = 64/V
And by substitution in equation (2)
V * (64/V) + 16* V = 384
64 + 16 *V = 384 ⇒ 16*V = 320 ⇒ V= 320/16
V = 20 miles /sec
Wind Energy is the kind of energy will Cassie uses to power the boat.
What is wind energy?
The method of producing electricity using air or wind currents that naturally occur in the earth's atmosphere is known as wind energy (or wind power). Electricity is produced by modern wind turbines that harness the kinetic energy of the wind. Wind passing across the turbine's blades is the initial step.
What is the major problem with wind energy?
Wind energy has the potential to have negative environmental effects, including the possibility of reducing, fragmenting, or deteriorating habitat for wildlife, fish, and plants, as with all energy supply choices. Furthermore, flying animals like birds and bats may be harmed by turbine blades in operation.
Learn more about wind energy: brainly.com/question/27997211
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