Answer:
Explanation:
The star is revolving the black hole like earth revolves around the sun .so time period of rotation T is given by the following relation
T² = 
, R is distance between black hole and star , M is mass of black hole
Given T = 4.8 hours
4.8² =
Using the same equation for earth sun system
24² = 
, Ms is mass of the sun and 50R is distance between the sun and the earth .
Dividing the equation
= 
= 2x 10⁻⁴
Answer:
d = 120 [m]
Explanation:
In order to solve this problem, we must use the theorem of work and energy conservation. Where the energy in the final state (when the skater stops) is equal to the sum of the mechanical energy in the initial state plus the work done on the skater in the initial state.
The mechanical energy is equal to the sum of the potential energy plus the kinetic energy. As the track is horizontal there is no unevenness, in this way, there is no potential energy.
E₁ + W₁₋₂ = E₂
where:
E₁ = mechanical energy in the initial state [J] (units of Joules)
W₁₋₂ = work done between the states 1 and 2 [J]
E₂ = mechanical energy in the final state = 0
E₁ = Ek = kinetic energy [J]
E₁ = 0.5*m*v²
where:
m = mass = 60 [kg]
v = initial velocity = 12 [m/s]
Now, the work done is given by the product of the friction force by the distance. In this case, the work is negative because the friction force is acting in opposite direction to the movement of the skater.
W₁₋₂ = -f*d
where:
f = friction force = 36 [N]
d = distance [m]
Now we have:
0.5*m*v² - (f*d) = 0
0.5*60*(12)² - (36*d) = 0
4320 = 36*d
d = 120 [m]
<span>500 hz means 500 times in a second therefore its 2.</span>
You have not provided choices, therefore, I can not provide an exact choice.
However, I will tell you the components of the given circuit and you can choose the one found in the choices you have.
The given circuit is composed of:
1- A battery:
It has the symbol of the long line and short line next to each other. The long line represents the positive pole while the short line represents the negative one. Battery is used to supply power to the circuit
2- An ammeter:
If has the symbol of an "A" in a circle. This device is used to measure the current flowing in the circuit
3- A resistance:
It has the symbol of the zigzag line. Resistance could be any device that consumes the power in the circuit.
4- A switch:
This has the symbol of the line at the bottom of the circuit. In its current status, the switch is off which means that no current is flowing in the circuit. If we connect the open terminal of the switch with the circuit, the switch is said to be on and current would flow in the circuit.
Hope this helps :)
MOLECULE;
For example, a hydrogen atom forms one bond, an oxygen atom forms two, and carbon forms four bonds. Look at that molecule of water again - each hydrogen has one bond, and the oxygen in the middle has two bonds. Molecules can be much bigger.
