A heavyweight boxer winds up and punches a punching bag. Which of the following are true? (Choose 2) A The punching bag exerts more force than the fist.
B The fist exerts more force than the punching bag.
The force acting on the bag is equal and opposite to the force acting on the fist.
D
The fist creates the action force and the punching bag creates the reaction force.
E There is no force between the two objects because they are balanced.

Why cooking gas has a typical smell

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.

When an object is heated it contracts. a. true b. false