Answer:
a) 6.7 * 10⁴ W b) 8.5* 10¹⁰ W/m²
Explanation:
a) The power of one laser pulse, by definition of power, is equal to the energy expended during the emission of the pulse, divided by the time during which the energy was present, as follows:
P = ΔE/Δt = 10⁻³ J / 15*10⁻⁹ sec = 6.7* 10⁴ W
b) The intensity, or power density, of the light wave, is just the power that we just calculated in a) divided by the cross-section area traversed by the pulse, which is a circle of 1.0 mm diameter.
So, we can write the following expression:
I = P/A = P / π*(d²/4) = 6.7*10⁴ W /( π*(10⁻³)²/4) m² = 8.5* 10¹⁰ W/m²
Answer:
If the frequency of a wave is doubled, what happens to its wavelength? If the frequency is doubled, the wavelength is only half as long.
Most pictures used as the milky way are actually just pictures of other galaxies (such as Andromeda) that we just figure are similar enough to ours.
<span>We can take a side ways photo of our own galaxy, but not a front view. </span>
<span>The absolute magnitude of a star is how bright it would appear to us
if it were located ten parsecs (about 32.6 light years) from us. So it's
a way of treating all stars equally ... on a "level playing field" ... and it
describes each star's actual brightness. </span>
The answer would be
Negative Acceleration
