Answer:
ωf = 0.16 rad/s
Explanation:
Moment of inertia of the child = mr² = 20(1.6²) = 51.2 kg•m²
Moment of Inertia of the MGR = ½mr² = ½(180)1.6² = 230.4 kg•m²
(ASSUMING it is a uniform disk)
Initial angular momentum of the child = Iω = I(v/r) = 51.2(1.4/1.6) = 44.8 kg•m²/s
Conservation of angular momentum
44.8 = (51.2 + 230.4)ωf
ωf = 0.15909090...
Answer:
4.62 s
Explanation:
We are given that
Initial angular speed,![\omega=3.4 rad/s](https://tex.z-dn.net/?f=%5Comega%3D3.4%20rad%2Fs)
![\theta=1\frac{1}{4} rev=\frac{5}{4}\times 2\pi=2.5\pi rad](https://tex.z-dn.net/?f=%5Ctheta%3D1%5Cfrac%7B1%7D%7B4%7D%20rev%3D%5Cfrac%7B5%7D%7B4%7D%5Ctimes%202%5Cpi%3D2.5%5Cpi%20rad)
![\omega'=0](https://tex.z-dn.net/?f=%5Comega%27%3D0)
![\omega'^2-\omega^2=2\alpha \theta](https://tex.z-dn.net/?f=%5Comega%27%5E2-%5Comega%5E2%3D2%5Calpha%20%5Ctheta)
Substitute the values
![0-(3.4)^2=2\times 2.5\pi \alpha](https://tex.z-dn.net/?f=0-%283.4%29%5E2%3D2%5Ctimes%202.5%5Cpi%20%5Calpha)
![\alpha=\frac{-(3.4)^2}{2\times 2.5\pi}=-0.736 rad/s^2](https://tex.z-dn.net/?f=%5Calpha%3D%5Cfrac%7B-%283.4%29%5E2%7D%7B2%5Ctimes%202.5%5Cpi%7D%3D-0.736%20rad%2Fs%5E2)
![\omega'=\omega+\alpha t](https://tex.z-dn.net/?f=%5Comega%27%3D%5Comega%2B%5Calpha%20t)
![0=3.4-0.736 t](https://tex.z-dn.net/?f=0%3D3.4-0.736%20t)
![-0.736t=-3.4](https://tex.z-dn.net/?f=-0.736t%3D-3.4)
![t=\frac{-3.4}{-0.736}=4.62 s](https://tex.z-dn.net/?f=t%3D%5Cfrac%7B-3.4%7D%7B-0.736%7D%3D4.62%20s)
Hence, the wheel takes 4.62 s to come to rest.
Newton's law of universal gravitation, says that every particle attracts every other particle in the universe with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.
Or in simple words, every particle in the world attracts each other to themselves, but the particle with most mass would attract with more force compared to a particle with less mass.
(<u><em>Please consider leaving a rate, a thanks and, a crown would be really appreciated! Thank you!</em></u>)
Answer:
it have Potential energy
Explanation:
given data
Drag the pendulum to an angle 30∘
to find out
what form of energy does it have
solution
we know that pendulum start no kinetic energy when it release from any rest position then in starting it have potential energy only so that when pendulum is angle 30∘ at some height from ground so when it start it have potential energy same as in starting.
we know that the total energy is always conserve
so it have potential energy