1. In Physics, we distinguish between wave motion and particle motion, Wave motion refers to the movement of a wave-like pattern from one location on the medium to another. When you
view a water wave moving along the surface of water, you are observing wave motion. There is
a very obvious movement of a collection of crests and troughs along the water surface. In the
Simple Wave Simulator, there is a collection of crests and troughs moving through a rope, this is
wave motion. But there are also three points on the rope that are colored red. When you
observe the motion of these points, you are observing particle motion - the motion of particles of
the rope. Describe the motion of these particles.

a.metals can become magnetic if they have many spinning electrons that create magnetic fields.d.only some metals are attracted by magnets; these metals are called ferromagnetic.

d.wrapping an insulated wire around a metal with ferromagnetic properties and applying an electric current.

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.