Hi there!
We can use the following (derived) equation to solve for the final velocity given height:
vf = √2gh
We can rearrange to solve for height:
vf² = 2gh
vf²/2g = h
Plug in the given values (g = 9.81 m/s²)
(13)²/2(9.81) = 8.614 m
We can calculate time using the equation:
vf = vi + at, where:
vi = initial velocity (since dropped from rest, = 0 m/s)
a = acceleration (in this instance, due to gravity)
Plug in values:
13 = at
13/a = t
13/9.81 = 1.325 sec
Answer:
Explain step by step
Explanation:
Collisions with asteroids, comets and other stuff from space have been responsible for huge landmarks in our planet’s history: global shifts in climate, the creation of our moon, the reshuffling of our deepest geology, and the extinction of species.
Asteroid threats pop up in the news every now and then, but the buzz tends to fizzle away as the projectiles pass us by. Other times, as with the 2013 Chelyabinsk meteor in Russia, we don’t know they’re here until they’re here.
Perhaps most useful to remember is that when near-Earth objects (including asteroids, comets and meteoroids) enter the atmosphere, they’re called meteors; and if there’s anything left when they hit the ground, the resulting object is called a meteorite. We tend to focus on asteroids when talking about potential collisions, because they’re more likely to hit us than other stuff like comets, but still big enough to pose a threat.
Answer:
521 nm
Explanation:
Given the values and units we are given, I'm assuming 5.76*10^14 Hz is frequency.
The formula to use here is λ * υ = c, where λ is wavelength, υ is frequency, and c is the speed of light.
λ = 
Explanation:
average speed = total distance travelled / total time travelled
time to travel the first 6km: 6 / 50 = 3/25 (h)
time to travel the next 6km: 6 / 90 = 1/15 (h)
[I think there's problem in the question 'cause 900km/h sounds impossible for normal person to travel in normal condition]
The total time: 3/25 + 1/15 = 14/75 (h)
Average speed over the 12 km drive will be:

less mass is more mass but less energy in more mass. less mass has more energy