A ball is dropped freely from the top of a ten-floor building in which each floor is measured to be 2 m. Then the velocity of the ball at which it would hit the ground is ?

19.80 m/s

Explanation:

From the question given above, the following data were obtained:

Height of each floor = 2 m

Total Height (h) = 2 × 10 = 20 m

Initial velocity (u) = 0 m/s

Acceleration due to gravity (g) = 9.8 m/s²

Final velocity (v) =?

The velocity at which the ball will hit the ground can be obtained as follow:

v² = u² + 2gh

v² = 0² + (2 × 9.8 × 20)

v² = 0 + 392

v² = 392

Take the square root of both side

v = √392

v = 19.80 m/s

Thus, the ball will hit the ground with a velocity of 19.80 m/s

absorption lines are where light has been absorbed by the atom thus you see a dip in the spectrum whereas.

emission spectra have spikes in the spectra due to atoms releasing photons at those wavelengths.

explanation: