Answer:
e.)At twice the distance, the strength of the field is E/4.
Explanation:
The strength of the electric field at a certain distance from a point charge is given by:
where
k is the Coulomb's constant
Q is the charge
r is the distance from the point charge
In this problem, the distance from the point charge is doubled:
r' = 2r
So the new electric field strength is
so, at twice the distance the strength of the field is E/4.
Answer:
Explanation:
In order to solve this problem, we can do an analysis of the energies involved in the system. Basically the addition of the initial potential energy of the spring and the kinetic energy of the mass should be the same as the addition of the final potential energy of the spring and the kinetic energy of the block. So we get the following equation:
In this case, since the block is moving from rest, the initial kinetic energy is zero. When the block loses contact with the spring, the final potential energy of the spring will be zero, so the equation simplifies to:
The initial potential energy of the spring is given by the equation:
the Kinetic energy of the block is then given by the equation:
so we can now set them both equal to each other, so we get:
This new equation can be simplified if we multiplied both sides of the equation by a 2, so we get:
so now we can solve this for the final velocity, so we get:
