Answer:
Hooke's law, given by 
is denoted with a negative sign to regard that the direction of restoring force that occurs opposite in direction of the force that caused the displacement 
. F represents the force required to create a spring displacement of .
Explanation:
As with many things in physics, the negative sign represents direction. In this case, after a spring is displaced a distance of from equilibrium, the restoring force created by the spring will be in opposite direction of the force applied to move the spring there, represented by F.
Answer:
E(final)/E(initial)=2
Explanation:
Applying the law of gauss to two parallel plates with charge density equal σ:
So, if the charge is doubled the Electric field is doubled too
E(final)/E(initial)=2
Answer:
In standard GR, nothing exists at the center of a black hole. The center of a black hole is a singularity, and because GR fails at that point it is simply removed from the manifold. That means that the singularity is not part of spacetime.
To answer your question more realistically, we believe that GR is an approximate theory that fails well before you reach the center. Unfortunately, we have no good alternative theory with which to answer the question in the region where GR fails. We simply don’t have any data from that regime and it is very hard to formulate a good theory without data. So there very well could be time at the center, but we simply don’t have a good way to even guess.
Answer:
a. 
b. 
Explanation:
Given:
The runner force average to find given the equations
a.
b.
Work done by the system by this force so
power=voltsxamps=watts.
12=3xamps
4 amps
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A. To increase the current, decrease the resistance.
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r=v/i = 53/7
