The acceleration due to gravity serves as the centripetal acceleration of the objects that orbits the Earth. The centripetal acceleration due to gravity is calculated through the equation,
a = v²/r
where v is the speed and r is the radius. Substituting the known values to the equation,
9.8 m/s² = (420 m/s)² / r
The value of r from the equation is 18000 m or equal to 18 km.
<em>Answer: 18 km</em>
You would have to run a little less than 2 blocks
The final velocity is 5.87 m/s
<u>Explanation:</u>
Given-
mass, 
= 72 kg
speed, 
= 5.8 m/s
,
= 45 kg
,
= 12 m/s
Θ = 60°
Final velocity, v = ?
Applying the conservation of momentum:
X + X = ( + ) v
72 X 5.8 + 45 X 12 X cos 60° = (72 + 45) v
v = 417.6 + 540 X 
v = 417.6 + 
v = 5.87 m/s
The final velocity is 5.87 m/s
Answer:
10
Explanation:
Lets say that a,b,c,d,e are the five allowed energy states in order of decreasing energy. Then the number of possible different spectral lines comes from the electron dropping from a high state to a lower state. So, they will do so in following ways:
a - b
a - c
a - d
a- e
b - c
b - d
b- e
c - d
c- e
d- e
Ans- Ten different possible energy jumps giving six different colors or lines in the spectrum.
The purpose of an experiment is to LEARN the EFFECT of something.
The way you do that is to CHANGE the thing and see what happens.
You can change as many things as you want to. But If you change
TWO things and observe the result, then you don't know which one
of them caused the effect you see.
Or maybe BOTH of them working together caused it. You don't know.
So your experiment is not really much good. You need to do it again.
