Acar moving south speeds up from 10 m/s to 40 m/s in 15 seconds. what is the car’s acceleration? a. 2 m/s2 b.15 m/s2 c.30 m/s2 d.50 m/s2

Acceleration,

Explanation:

It is given that,

A car moving south speeds up from 10 m/s to 40 m/s in 15 seconds.

It means,

Initial velocity of the car, u = 10 m/s

Final velocity of the car, v = 40 m/s

Time taken, t = 15 seconds

We have to find the acceleration of the car. Mathematically, acceleration of the car is given by taking difference in velocities divided by time taken i.e.

Hence, this is the required solution.

i would think klcio3

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.