Physics · Electrostatics
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If the distance between two point charges is halved, the force between them would be ___.
- A
Half
- B
Double
- C
One fourth
- D
Four times
The force between two point charges is given by Coulomb's law:
F = (kq1q2)/r2
where F is the force, q1 and q2 are the charges, r is the distance between them, and k is the Coulomb constant.
If the distance between the two charges is halved (i.e., r is divided by 2), then the force between them becomes:
F' = (kq1q2)/(r/2)2
F' = (kq1q2)/(r2/4)
F' = 4xkq1q2)/r2
F' = 4F
Thus, the force between the two charges is quadrupled (i.e., becomes four times as much) if the distance between them is halved
Incorrect as per formulaThe force between two point charges is given by Coulomb's law:
F = (kq1q2)/r2
where F is the force, q1 and q2 are the charges, r is the distance between them, and k is the Coulomb constant.
If the distance between the two charges is halved (i.e., r is divided by 2), then the force between them becomes:
F' = (kq1q2)/(r/2)2
F' = (kq1q2)/(r2/4)
F' = 4x(kq1q2)/r2
F' = 4F
Thus, the force between the two charges is quadrupled (i.e., becomes four times as much) if the distance between them is halved.
Incorrect as per formulaThe force between two point charges is given by Coulomb's law:
F = (kq1q2)/r2
where F is the force, q1 and q2 are the charges, r is the distance between them, and k is the Coulomb constant.
If the distance between the two charges is halved (i.e., r is divided by 2), then the force between them becomes:
F' = (kq1q2)/(r/2)2
F' = (kq1q2)/(r2/4)
F' = 4x(kq1q2)/r2
F' = 4F
Thus, the force between the two charges is quadrupled (i.e., becomes four times as much) if the distance between them is halved.
Incorrect as per formulaThe force between two point charges is given by Coulomb's law:
F = (kq1q2)/r2
where F is the force, q1 and q2 are the charges, r is the distance between them, and k is the Coulomb constant.
If the distance between the two charges is halved (i.e., r is divided by 2), then the force between them becomes:
F' = (kq1q2)/(r/2)2
F' = (kq1q2)/(r2/4)
F' = 4x(kq1q2)/r2
F' = 4F
Thus, the force between the two charges is quadrupled (i.e., becomes four times as much) if the distance between them is halved.
The force between two point charges is given by Coulomb's law:
F = (kq1q2)/r2
where F is the force, q1 and q2 are the charges, r is the distance between them, and k is the Coulomb constant.
If the distance between the two charges is halved (i.e., r is divided by 2), then the force between them becomes:
F' = (kq1q2)/(r/2)2
F' = (kq1q2)/(r2/4)
F' = 4x(kq1q2)/r2
F' = 4F
Thus, the force between the two charges is quadrupled (i.e., becomes four times as much) if the distance between them is halved.
Tagged under Physics · Electrostatics · 2021