Answer:
![V=\dfrac{3}{2}\ m/s](https://tex.z-dn.net/?f=V%3D%5Cdfrac%7B3%7D%7B2%7D%5C%20m%2Fs)
Explanation:
Two identical bodies are sliding toward each other on a frictionless surface.
Initial speed of body 1, m₁ = 1 m/s
Initial speed of body 2, m₂ = 2 m/s
They collide and stick.
We need to find the speed of the combined mass. Let V is the speed of the combined mass.
Using the conservation of momentum.
![m_1u_1+m_2u_2=V(m_1+m_2)](https://tex.z-dn.net/?f=m_1u_1%2Bm_2u_2%3DV%28m_1%2Bm_2%29)
We have, m₁ = m₂ = m
![m\times 1+m\times 2=(m+m)V\\\\m+2m=2m\times V\\\\3m=2mV\\\\V=\dfrac{3}{2}\ m/s](https://tex.z-dn.net/?f=m%5Ctimes%201%2Bm%5Ctimes%202%3D%28m%2Bm%29V%5C%5C%5C%5Cm%2B2m%3D2m%5Ctimes%20V%5C%5C%5C%5C3m%3D2mV%5C%5C%5C%5CV%3D%5Cdfrac%7B3%7D%7B2%7D%5C%20m%2Fs)
So, the speed of the combined mass is
.
The formula is
F_grav = G * m1 * m2 / r^2
G m1 and m2 are going to stay the same once chosen no matter what the distance is. The only thing that will change is the distance.
As the distance increases, the Gravitational Force will decrease. It will decrease by quite a bit.
As the distance decreases, the gravitational force will Increase.
The relationship is inverse. The moon travelling around the earth is one example. The earth travelling around the sun is another.
Answer:
at the speed of light (
)
Explanation:
The second postulate of the theory of the special relativity from Einstein states that:
"The speed of light in free space has the same value c in all inertial frames of reference, where
"
This means that it doesn't matter if the observer is moving or not relative to the source of ligth: he will always observe light moving at the same speed, c.
In this problem, we have a starship emitting a laser beam (which is an electromagnetic wave, so it travels at the speed of light). The startship is moving relative to the Earth with a speed of 2.0*10^8 m/s: however, this is irrelevant for the exercise, because according to the postulate we mentioned above, an observer on Earth will observe the laser beam approaching Earth with a speed of
.
Answer: It is both B and D
Select all that apply.
At night, thermal energy moves _____.
from space to the atmosphere
from the land to the atmosphere
from the atmosphere to the land
from the atmosphere to space