When rubbing a balloon against your head, you notice the balloon pulling your hair away from your head. What best explains why the balloon and your hair are attracted to each other? They become oppositely charged, which causes them to be attracted to each other.

They become similarly charged, which causes them to be attracted to each other.

They stick together because of the friction between the two objects.

They are made of different materials, which is why they attract each other.

Suppose that an electromagnetic wave which is linearly polarized along the x−axis is propagating in vacuum along the z−axis. the wave is incident on a conductor which is placed at z > 0 region of the space. the conductor has conductivity σ, magnetic permeability µ and electric permittivity ε. (a) find the characteristic time for the free charge density which dissipates at the conductor. (b) write the maxwell equations and derive the wave equation for a plane wave propagating in a conductor. (c) find the attenuation distance at which the incident amplitude reduces to e ^−1 of its initial value. (d) find the electric and magnetic fields inside the conductor. 8 (e) find the power loss per area of the incident electromagnetic wave at the surface of conductor.

All the simple machines make work easier to do by changing the or of a force. a. size; type b. work; type c. size; direction d. type; direction

Which are advantages of renewable resources? check all that apply. renewable energy supplies are completely reliable everywhere. some renewable resources will never be used up. little or no waste is produced by renewable resource plants. electricity can be generated in large quantities. many renewable energy facilities have lower operating costs.