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A bat chasing a moth emits a sequence of three chirps every 0.010 seconds and
later hears the echos of the chirps as detailed in the diagram below.
Click!
Click!
Click!
Echo!
Echo! Echo!
++
0.09s
Time:
Os 0.01s 0.02s
0.095s 0.10s
Question: How far away is the moth when the bat hears the third echo?
Make sure to explain how you arrived at your answer.

Acar travels along a highway with a velocity of 24 m/s, west. the car exits the highway; and 4.0 s later, its instantaneous velocity is 16 m/s, 45° north of west. what is the magnitude of the average acceleration of the car during the four-second interval?

To do work, this truck uses energy stored in chemical fuel and an electrical battery. how much total energy does this truck put out?

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.