A projectile fired upward from the Earth's surface will usually slow down, come momentarily to rest, and return to Earth. For a certain initial speed, however it will move upward forever, with its speed gradually decreasing to zero just as its distance from Earth approaches infinity. The initial speed for this case is called escape velocity. You can find the escape velocity v for the Earth or any other planet from which a projectile might be launched using conservation of energy. The projectile of mass m leaves the surface of the body of mass M and radius R with a kinetic energy Ki = mv²/2 and potential energy Ui = -GMm/R. When the projectile reaches infinity, it has zero potential energy and zero kinetic energy since we are seeking the minimum speed for escape. Thus Uf = 0 and Kf = 0. And from conservation of energy,
Ki + Ui = Kf + Uf
mv²/2 -GMm/R = 0
∴ v = √(2GM/R)
This is the expression for escape velocity.
Answer:
Inducted Magnetic field will be toward from you
Inducted current direction will be counter clockwise.
Explanation:
Lenz's law states that the direction of the current induced in a wire by a changing magnetic field is such that the magnetic field created by the induced current opposes the initial changing magnetic field.
So if the field begins to decrease, the induced magnetic field would try to stop this, so its direction will be the same as the magnetic field, toward from you.
This induced magnetic field is produced by the current in the wire. If the inducted magnetic field will be toward you, the right hand rule says that the direction from the inducted current will be counter clockwise.
Answer:
V = 0
Explanation:
To find the potential at the middle of the two charges with opposite signs, you use the following formula:
(1)
where you have used the fact that the charges are the same and the distances are the same.
The electric potential is zero at the point in the middle of the two charges
Your grade will probably go down to a D 68% or little higher than that
Answer:
a)
For this case we know the following values:
So then if we replace we got:
b)
With
And replacing we have:
And then the scattered wavelength is given by:
And the energy of the scattered photon is given by:
c)
Explanation
Part a
For this case we can use the Compton shift equation given by:
For this case we know the following values:
So then if we replace we got:
Part b
For this cas we can calculate the wavelength of the phton with this formula:
With
And replacing we have:
And then the scattered wavelength is given by:
And the energy of the scattered photon is given by:
Part c
For this case we know that all the neergy lost by the photon neds to go into the recoiling electron so then we have this: