A rock is thrown off a cliff with a speed of 5 m/s downward. How far will it fall after 7 seconds have elapsed?

Distance traveled is the average velocity times time.  When something is dropped (or thrown), it accelerates downward in accord with the acceleration of gravity ( g = 9.8m/sec2)

The increase in velocity while falling is simply t * 9.8,  t = 2, so the increase is 19.6 m/s.  The initial velocity is 3, so the final is 22.6, and the average is 25.6/2 = 12.8m/s

Therefore, d = v(average) * t = 12.8 * 2 = 25.6m

The equivalent formula is:

d = v(initial)*t + (a*t2) / 2

d = 3*2 + 4.9 * 4 = 25.6

Explanation:

Distance traveled is the average velocity times time.  When something is dropped (or thrown), it accelerates downward in accord with the acceleration of gravity ( g = 9.8m/sec2)

The increase in velocity while falling is simply t * 9.8,  t = 2, so the increase is 19.6 m/s.  The initial velocity is 3, so the final is 22.6, and the average is 25.6/2 = 12.8m/s

Therefore, d = v(average) * t = 12.8 * 2 = 25.6m

The equivalent formula is:

d = v(initial)*t + (a*t2) / 2

d = 3*2 + 4.9 * 4 = 25.6

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:

if the person is shown to have +90n, then ans is -10n.

if the person is shown to have -90n, then ans is +10n.