Answer:
The mechanical energy of the satellite is about 12 Gigajoules
Explanation:
The total mechanical energy is the sum of the kinetic and potential energy:
While we can determine the potential energy from the given values (height above earth's surface), to calculate the kinetic energy the velocity of the satellite needs to be determined first.
The formula for orbital velocity is:
with G the gravitational constant, m_E the mass of the Earth, and r the satellite distance measured from the center of the Earth:
This velocity points in the direction of the tangent of the orbit.
Now the kinetic and total mechanical energy can be calculated:
The mechanical energy of the satellite is about 12 Gigajoules
Answer:
the answer is the explaination
Explanation:
Present beach erosion prevention methods include sand dunes, vegetation, seawalls, sandbags, and sand fences. Based on the research conducted, it is evident that new ways to prevent erosion must be obtained. Each way that is currently used has extensive negative effects on beaches and their natural tendencies.
Well, I'll try to write the formula in a way that's not confusing,
but I'm afraid it might be slightly confusing anyway.
When you're working with dB, the basic rule is
A change of 10 dB means either multiplying or dividing by 10 .
Multiply something by 10 ==> it increases by 10 dB.
Divide something by 10 ==> it decreases by 10 dB.
It turns out that another way to write all of this is . . .
An increase of 10 dB ===> multiply the original amount by 10¹
An increase of 20 dB ===> multiply the original amount by 10²
An increase of, say, 7 dB ===> multiply the original amount by 10⁰·⁷
A decrease of 10 dB ===> multiply the original amount by 10⁻¹
A decrease of 30 dB ===> multiply the original amount by 10⁻³
A decrease of, say, 13 dB ===> multiply the original amount by 10⁻¹·³
This question says: The sound increases by 5 dB .
That means the original 'intensity' or 'power' of the sound
is multiplied by
10⁰·⁵ = √10 = about 3.162 (rounded) .
From the choices listed, the closest one is (c).
The resultant in the x-direction:
Rx = F1 + F2 = 2.5 N - 1 N = 1.5 N .
The resultant in the y-direction:
Ry = F3 + F4 = 2 N - 3 N = -1 N.
