The atoms of some materials have no free electrons in their outer orbits. These electrons are busy doing other jobs, like being shared in the orbits of two adjacent atoms. They are so closely held that it is very difficult to pull them away. Most compounds of carbon and hydrogen are like this.
<span>Plastics, whose molecules are made from long combinations of carbon and hydrogen atoms, have few or no free electrons. This means that plastics are poor conductors of electricity (and they are also poor conductors of heat). hope that helped.</span>
Answer: c
Explanation: it is c because i used my brain to answer it
Explanation:
Below is an attachment containing the solution.
(a) ![x = \frac{m_2L}{m_1+m_2}](https://tex.z-dn.net/?f=x%20%3D%20%5Cfrac%7Bm_2L%7D%7Bm_1%2Bm_2%7D)
<u>Explanation:</u>
Given:
Moment of Inertia of m₁ about the axis, I₁ = m₁x²
Moment of Inertia of m₂ about the axis. I₂ = m₂ (L - x)²
Kinetic energy is rotational.
Total kinetic energy is ![E = \frac{1}{2} I_1w_0^2 + \frac{1}{2}I_2w_0^2 = \frac{1}{2} w_0^2(m_1x^2 + m_2(L-x)^2)](https://tex.z-dn.net/?f=E%20%3D%20%5Cfrac%7B1%7D%7B2%7D%20I_1w_0%5E2%20%2B%20%5Cfrac%7B1%7D%7B2%7DI_2w_0%5E2%20%3D%20%5Cfrac%7B1%7D%7B2%7D%20w_0%5E2%28m_1x%5E2%20%2B%20m_2%28L-x%29%5E2%29)
Work done is change in kinetic energy.
To minimize E, differentiate wrt x and equate to zero.
![m_1x - m_2(L-x) = 0\\\\x = \frac{m_2L}{m_1+m_2}](https://tex.z-dn.net/?f=m_1x%20-%20m_2%28L-x%29%20%3D%200%5C%5C%5C%5Cx%20%3D%20%5Cfrac%7Bm_2L%7D%7Bm_1%2Bm_2%7D)
Alternatively, work done is minimum when the axis passes through the center of mass.
Center of mass is at ![\frac{m_2L}{m_1 + m_2}](https://tex.z-dn.net/?f=%5Cfrac%7Bm_2L%7D%7Bm_1%20%2B%20m_2%7D)