Answer:
Velocity=14[m/s]
Explanation:
We can solve this problem by using the principle of energy conservation, where potential energy becomes kinetic energy.
In the attached image we can see the illustration of the ball falling from the height of 20 meters, at this time the potential energy will have the following value.
![Ep=m*g*h\\where:\\m=3[kg]\\h=20[m]\\](https://tex.z-dn.net/?f=Ep%3Dm%2Ag%2Ah%5C%5Cwhere%3A%5C%5Cm%3D3%5Bkg%5D%5C%5Ch%3D20%5Bm%5D%5C%5C)
![Ep=3*9.81*20\\Ep=588.6[J]](https://tex.z-dn.net/?f=Ep%3D3%2A9.81%2A20%5C%5CEp%3D588.6%5BJ%5D)
When the ball passes through half of the distance (10m) its potential energy will have decreased by half as shown below.
![Ep=3*9.81*10\\Ep=294.3[m]](https://tex.z-dn.net/?f=Ep%3D3%2A9.81%2A10%5C%5CEp%3D294.3%5Bm%5D)
If we know that potential energy is transformed into kinetic energy, we can find the value of speed.
![Ek=\frac{1}{2} *m*v^{2} \\therefore\\v=\sqrt{\frac{Ek*2}{m} } \\v=\sqrt{\frac{294.3*2}{3} } \\\\v=14[m/s]](https://tex.z-dn.net/?f=Ek%3D%5Cfrac%7B1%7D%7B2%7D%20%2Am%2Av%5E%7B2%7D%20%5C%5Ctherefore%5C%5Cv%3D%5Csqrt%7B%5Cfrac%7BEk%2A2%7D%7Bm%7D%20%7D%20%5C%5Cv%3D%5Csqrt%7B%5Cfrac%7B294.3%2A2%7D%7B3%7D%20%7D%20%5C%5C%5C%5Cv%3D14%5Bm%2Fs%5D)
Answer:
Vf₂ = 2 Vf₁
It shows that final speed of Joe is twice the final speed of Jim.
Explanation:
First, we analyze the final speed of Jim by using first equation of motion:
Vf₁ = Vi + at
where,
Vf₁ = final speed of Jim
Vi = initial speed of Jim = 0 m/s
a = acceleration of Jim
t = time of acceleration for Jim
Therefore,
Vf₁ = at ---------------- equation (1)
Now, we see the final speed of Joe. For Joe the parameters will become:
Vf = Vf₂
Vi = 0 m/s
a = a
t = 2t
Therefore,
Vf₂ = 2at
using equation (1):
<u>Vf₂ = 2 Vf₁</u>
<u>It shows that final speed of Joe is twice the final speed of Jim.</u>
I am not sure how you want me to answer this, but yes, gas can go from being a gas to a liquid when the right temp and pressure is applied.
There are many people in the city and so much traffic that it pollutes the air and makes it warmer where the country dosent have much traffic so there for its cooler