Afootball player pushes against another player trying to block him from moving any farther down the field. which term best describes this example?

negative work
positive work
negative force
positive force

is it b or something else? ? i really need this to be right. you!

its a negative work, not a negative force

Explanation:

I took the quiz first i put negative force i got it wrong

then when i put negative work it was right

Hope it help:)

i think the answer would be reserve.

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.