The kinetic energy of a moving object is given by
where m is the object's mass and v its velocity.
In our problem, the initial kinetic energy is:
while the final kinetic energy is:
So, the kinetic energy lost by Lucy and her bike is
Well, the lines of workings are cut off in the middle, and there's no 2nd image.
But I think it must have to do with the "cos" terms at the right end of the picture.
I'm guessing now, because the part I'm interested in would be just past the edge, where we can't see it.
I <em>think</em> that the first line says "cos(some angle)", and at the same place in the second line it says "cos(180 - the same angle)".
If that's what it says, then that's your answer, because cos(anything) is equal to the <em>negative</em> of cos(180 - the same thing).
That's the best I can do for you just now. Honestly, I don't see the connection yet between the question Dave is working on and the two lines I see in the picture.
Answer:
F = 7.50 10⁻⁶ N
Explanation:
The force of attraction between two bodies is given by the law of universal gravitation
F =
where m₁ and m₂ are the masses of the hides, r the distance that separates them and G the constant of attraction that is worth 6.67 10⁻¹¹ N m²/kg²
let's calculate
F = 6.67 10⁻¹¹ 500 900/2²
F = 7.50 10⁻⁶ N
A radioactive isotope will release alpha particles and become more stable, and becomes a different element.
If the distance is in km and time is in hours, then the speed is km/hr.
If the distance is in m and the time is in seconds, then the speed is m/sec.