If a word problem gives the separation distance between two charges in centimeters (cm), you should . Question 4 options:

1) enter that value directly since cm is the standard unit
2) convert that distance to inches, the standard unit
3) convert that distance to meters, the standard unit
4) convert that distance to whatever units are given in the second distance
5) look to see whether the charges are like or opposite to know what to do

3

Explanation:

Convert the distance to meters,the standard units.

the device is called “ rocket engine”

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.