Answer:

Explanation:
The electric force between two charged objects is given by:

where:
k is the Coulomb's constant
q1 and q2 are the charges of the two objects
r is their separation
In this problem:
q1 = 2.0 C
q2 = 1.0 C
r = 2 m
So, the electric force is

Answer: The time period of the given wave with frequency of 425 Hertz is 0.0023 seconds.
Explanation:
Frequency of the wave = 425 Hertz =


The time period of the given wave with frequency of 425 Hertz is 0.0023 seconds.
Answer:
Bowling Ball
Explanation:
The potential energy depends on the factors: mass of the object and distance between the two objects. In this case the distance is between the ground and the balls. Here, the bowling ball is heaviest and its center of mass is farthest in comparison to other two balls. Thus, it has the greatest potential energy.
The electron is accelerated through a potential difference of

, so the kinetic energy gained by the electron is equal to its variation of electrical potential energy:

where
m is the electron mass
v is the final speed of the electron
e is the electron charge

is the potential difference
Re-arranging this equation, we can find the speed of the electron before entering the magnetic field:

Now the electron enters the magnetic field. The Lorentz force provides the centripetal force that keeps the electron in circular orbit:

where B is the intensity of the magnetic field and r is the orbital radius. Since the radius is r=25 cm=0.25 m, we can re-arrange this equation to find B: