Answer:
h = 22.35 m
Explanation:
given,
initial speed of the rock,u = 0 m/s
length of the window,l = 2.7 m
time taken to cross the window,t = 0.129 s
Speed of the rock when it crosses the window


v = 20.93 m/s
height of the building above the window
using equation of motion
v² = u² + 2 g h
20.93² = 0² + 2 x 9.8 x h
h = 22.35 m
Hence, the height of the building above the top of window is equal to h = 22.35 m
<span>Let's convert the speed to m/s:
speed = (55 mph) (1609.3 m / mile) (1 hour / 3600 seconds)
speed = 24.59 m/s
Let's convert the mass to kilograms:
mass = (2135 lb) (0.45359 kg / lb)
mass = 968.4 kg
We can find the kinetic energy KE:
KE = (1/2) m v^2
KE = (1/2) (968.4 kg) (24.59 m/s)^2
KE = 292780 joules
The kinetic energy of the automobile is 292780 joules.</span>
Answer:
Explanation:
We can use the conservation of the angular momentum.


Now the Inertia is I(professor_stool) plus mR², that is the momentum inertia of a hoop about central axis.
So we will have:

Now, we just need to solve it for ω.

I hope it helps you!
Wave power can be regarded as a reliable source of energy because the ocean currents are always moving.
<h3>What can be the challenges of wave power?</h3>
Wave power is a device that can be used to convert the mechanical energy of the ocean waves into electrical energy based on the principle of conservation of energy.
The major challenges that face the use of wave power in electricity generation is the unreliability of the waves which leads to uncertainty in the quantity of power generated Also, the wave direction and direction of ocean currents all limit the amount of power generated by this method. However, in spite of challenges, it can be regarded as a reliable source of energy because the ocean currents are always moving.
Learn more about wave power:brainly.com/question/1362067
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