Afish tank initially contains 35 liters of pure water. brine of constant, but unknown, concentration of salt is flowing in at 2 liters per minute. the solution is mixed well and drained at 2 liters per minute. be the amount of salt, in grams, in the fish tank after minutes have elapsed. find a formula for the rate of change in the amount of salt, da/dt, in a. let and the unknown concentration of incoming brine c. the amount f salt in the solution terms da grams/minute dt b. find a formula for the amount of salt, in grams, after t minutes have elapsed. your answer should be in terms of c and t (t grams c. in 40 minutes there are 20 grams of salt in the fish tank. what is the concentration of salt in the incoming brine?

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.

The free body diagram shows a box being pulled to the left up a 25-degree incline. the magnitude of the normal force is

You are a researcher for a golf club manufacturer. you are given two identical looking cubes of a metal alloy. you are informed that they are made of the exact same material, but one is crystalline, whereas the other is amorphous. it is your job to determine which one is amorphous this one is more stress-resistant and is useful in reinforcing golf clubs. which of the following is the best way to determine which is which? a. determine the density of each cube. the more dense one is the amorphous solid. b. melt both cubes and look for a broader range of melting temperatures. the one that melts over a broader range of temperatures is the amorphous solid. c. determine the density of each cube. the less dense cube is the amorphous solid. d. melt both cubes and measure the range of melting temperatures. the one that melts over a narrower range of temperatures is the amorphous solid.