A liquid filled sealed system has cylinders with movable pistons on each end. The face of one piston has an area of 5 cm². The other piston has an area of 500 cm² and is supporting a weight of 2 kN on it. What force must be applied to the small cylinder to hold the weight up?
a. 200N
b. none of these
c. 2000 N
d. 20N

Which type of microscope would allow the viewer to see ribosomes inside a cell?

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.

Who was the first scientist to measure speed as distance over time?