7: A block is kicked along a horizontal rough surface, p=0.2, with an iniital speed 5 m/s. the box travels a
distance 10 m before coming to rest. You can assume constant acceleration lal.
A: What is the position of the block when the speed is 2.5 m/s.
B: at the point on the diagram denoted by the star where speed is 2.5 m/s, please sketch the vectors for
v, a, and Ax.
C: please describe how the point where v = 2.5 m/s changes if u were to double to 0.4.

waves moving from a fast medium to a slow medium will experience a reflection as light travels more slowly than red light. total internal reflection occurs when the critical angle is.

i'm on my way to history not a mistory.

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.