p=F/A
or,P=d×V×G/A (m=d×V)
or,p= d× A×h×g/A (A and A are cut)
or,P=d×H×G
Answer: 71.7 KJ
Explanation:
The rotational kinetic energy of a rotating body can be written as follows:
Krot = ½ I ω2
Now, any point on the rim of the flywheel, is acted by a centripetal force, according to Newton’s 2nd Law, as follows:
Fc = m. ac
It can be showed that the centripetal acceleration, is related with the angular velocity and the radius, as follows:
ac = ω2 r
We know that this acceleration has a limit value, so , we can take this limit to obtain a maximum value for the angular velocity also.
As the flywheel is a solid disk, the rotational inertia I is just ½ m r2.
Replacing in the expression for the Krot, we have:
Krot= ½ (1/2 mr2.ac/r) = ¼ mr ac = ¼ 67.0 Kg. 1.22 m . 3,510 m/s2 = 71. 7 KJ
<span>Organelles which are very important
in giving nutrients. During cellular respiration, the food molecules such as
glucose, are oxidized to carbon dioxide (CO2) and water (H2O) and trapped in
ATP (Adenosine triphosphate) form for further us of cell’s activities. ATP’s
are formed at mitochondria – the cell’s powerhouse. This type of organelle
takes and breaks nutrients absorbed by the cell and creates energy afterward.
The energy from ATP is then used by the body in kinetic activities like running
& walking or involuntary activities like breathing, blood circulation,
stimulus-responding, etc.</span>
All that business about the crane and the rope and the falling
is only there to confuse us.
The piano ended up 5 meters above the ground.
Potential energy = (mass) (gravity) (height)
= (200 kg) (9.81 m/s²) (5 m)
= (200 · 9.81 · 5) (kg-m²/s²)
= 9,810 joules .
