This would be called the "Escape Velocity "
In the absence of gravity, t<span>he rocks and debris
would never accrete into a planet. (B)
Also by the way, it wouldn't matter much, because
there wouldn't be a star to orbit around, AND orbits
wouldn't exist either.</span>
Answer:
∑ τ =0, L₀ = 
Explanation:
In a circular turning movement, when the arms are extended and then contracted in two possibilities:
- They are lowered the force of gravity is what pulls them, the tension of the muscle becomes zero to allow this movement.
In this movement the force is vertical(gravity) and the movement of the center of mass of each arm is vertical, so that the work is the weight value of the arm by the distance traveled by the center of mass.
- Another possibility is that the arms have stuck to the body, in this case the person's muscles perform the force, this force is horizontal and the displacement is the horizontal of the center of mass of the arms from the extended position to the contracted
In these movements the torque of the external force is equal for each arm, but in the opposite direction, so they are canceled where a net torque of zero, this causes the angular momentum to be preserved, which changes is the moment of inertia of the system and therefore you must also change the angular velocity to keep your product constant
∑ τ =0
L₀ = 
I₀ w₀ = I w
Answer: C.
Explanation:
For a parallel-plate capacitor where the distance between the plates is d.
The capacitance is:
C = e*A/d
You can see that the distance is in the denominator, then if we double the distance, the capacitance halves.
Now, the stored energy can be written as:
E = (1/2)*Q^2/C
Now you can see that in this case, the capacitance is in the denominator, then we can rewrite this as:
E = (1/2)*Q^2*d/(e*A)
e is a constant, A is the area of the plates, that is also constant, and Q is the charge, that can not change because the capacitor is disconnected.
Then we can define:
K = (1/2)*Q^2/(e*A)
And now we can write the energy as:
E = K*d
Then the energy is proportional to the distance between the plates, this means that if we double the distance, we also double the energy.