Answer: A) 
Explanation:
The equation for the moment of inertia 
of a sphere is:
(1)
Where:
is the moment of inertia of the planet (assumed with the shape of a sphere)
is the mass of the planet
is the radius of the planet
Isolating from (1):
(2)
Solving:
(3)
Finally:
Therefore, the correct option is A.
Answer:A converging lens is thickest in the middle and causes parallel light rays to converge through the focal point on the opposite side of the lens. A diverging lens is thinner in the middle and causes parallel light rays to diverge away from the focal point on the same side of the lens.
Explanation:
She does 200J .
We know she uses 20N of force and 10m is the distance. We multiply both numbers and we are given our answer of 200J. Hope this was helpful. :)
Answer:
b)
Explanation:
Normal force, is always directed upward the surface over which is placed the object, and can adopt any value, as required to meet Newton's 2nd Law.
In this case, as the external force on the suitcase pulls upward, in order to counteract the influence of gravity, normal force is less than the weight of the suitcase, as follows:
F + Fn = m*g
⇒ Fn = m*g - F
So, the normal force is equal to the magnitude of the weight of the suitcase (m*g) minus the magnitude of the force of the pull (F) which is the same expressed by the statement b.
Answer:
A
Explanation:
Begin as protostars, which fire up when they collapse and become denser and hotter.
