Answer:
Its velocity and acceleration are both nonzero.
Explanation:
The path of the wrench is trajectory while the acceleration due to Moon's gravity is acting on it.
As the velocity follows the path, as soon as it reaches maximum height, the vertical component of velocity is zero but the horizontal component is still there, constant.
Answer:
Explanation:
In this problem we can use Bohr's atomic model, to deal with the electronic transition, so we can have transitions between two given states.
ΔE =
-E₀
Lower state final state energy
Fundamental first excited state ΔE₁ = -2.4 - (-4.7) = 2.3 eV
Fundamental second excited state ΔE₂ = -1.0 - (-4.7) = 3.7 eV
Fundamental third excited state ΔE₃ = -0.3 - (-4.7) = 4.4 eV
As they indicate that there are no electrons in the excited states these are the only possible transitions.
When a wide range of light strikes, the frequencies of these energies are absorbed and observed as black bands (absence of radiation) in the spectrum.
Answer:
Kinetic energy of the electron 
Explanation:
It is given that,
Initial speed of an electron, u = 660000 m/s
Final speed of the electron, v = 0 (at rest)
The kinetic energy of an electron is possessed due to the motion of an electron. The mathematical formula for the kinetic energy is given by :

m is the mass of electron


Since, 


So, the initial kinetic energy of the electron is 1.23 eV. Hence, this is the required solution.
Answer:
1.117935:1
Explanation:
Since the wires are of the same material, they will have the same resistivity
.
The cross-sectional area of the of a wire is given by;

where d is the diameter of the wire.
Also, the relationship between resistance R, cross-sectional area A and length l of a wire is given as follows;

Since the resistivity same for both wires, say wire 1 and wire 2, we can wreite the following;

Hence from eqaution (3), the ration of wire 1 to 2 is expressed as;

Given;


We then use equation (1) to fine the ratio of the area
to 
bearing in mind that 
This ratio gives 0.8281. Substituting this into equation (5), we get the following;

B. A book sitting on a shelf. The books force is going down while the shelf's force is moving up against the book at an equal force.The answer would be B.