Answer:
Black holes are detected as surrounding material (like gas) is funnelled by the force of gravity into a disk around the black hole. The gas molecules in the disk swirl around the black hole so fast that they heat up and emit X-rays. These X-rays can be detected from Earth.
Explanation:
Answer:
θ = 14.27°
Explanation:
The only force acting on the puck is the gravitational force. Since the track is banked with an angle θ, we have to separate the components of the weight.
For the sake of simplicity, I will denote the perpendicular direction to the truck as the y-direction, and the direction along the radius as the x-direction.
So, the free-body diagram of the puck is as follows:
1- x-component of the weight of the puck: mgsinθ
2- y-component of the weight of the puck: mgcosθ
3- Normal force in the y-direction perpendicular to the track.
Since there is no motion on the y-direction, normal force is equal to the y-component of the weight of the puck.
The x-component of the weight of the puck is equal to the centripetal force according to Newton's Second Law:
Substituting the variables given in the question, the angle of the track can be found:
Answer:
Ionization potential of C⁺⁵ is 489.6 eV.
Wavelength of the transition from n=3 to n=2 is 1.83 x 10⁻⁸ m.
Explanation:
The ionization potential of hydrogen like atoms is given by the relation :
.....(1)
Here <em>E</em> is ionization potential, <em>Z</em> is atomic number and <em>n</em> is the principal quantum number which represents the state of the atom.
In this problem, the ionization potential of Carbon atom is to determine.
So, substitute 6 for <em>Z</em> and 1 for <em>n</em> in the equation (1).
<em> E = </em>489.6 eV
The wavelength (λ) of the photon due to the transition of electrons in Hydrogen like atom is given by the relation :
......(2)
R is Rydberg constant, n₁ and n₂ are the transition states of the atom.
Substitute 6 for Z, 2 for n₁, 3 for n₂ and 1.09 x 10⁷ m⁻¹ for R in equation (2).
= 5.45 x 10⁷
λ = 1.83 x 10⁻⁸ m
(a) 907.5 N/m
The force applied to the spring is equal to the weight of the object suspended on it, so:
The spring obeys Hook's law:
where k is the spring constant and is the stretching of the spring. Since we know , we can re-arrange the equation to find the spring constant:
(b) 1.45 cm
In this second case, the force applied to the spring will be different, since the weight of the new object is different:
So, by applying Hook's law again, we can find the new stretching of the spring (using the value of the spring constant that we found in the previous part):
(c) 3.5 J
The amount of work that must be done to stretch the string by a distance is equal to the elastic potential energy stored by the spring, given by:
Substituting k=907.5 N/m and , we find the amount of work that must be done: