Charges of +3 µC and –5 µC are 2 mm from each other. The –5 µC charge is replaced with a +5 µC charge. How will the electrical force between the charges compare with the original force?

same force, but in the opposite direction
same force, but in the same direction
greater force, but in the opposite direction
greater force, but in the same direction

same force in opposite direction.

Explanation: Charges of opposite sign attracts each other and charges with same sign repel each other. Because only sign of negative charge changes, and absolute value of charge remains same, value of force is same but is in opposite direction.

A) same force, but in the opposite direction

Explanation:

he's right

what was the acceleration of the 2 kg cart?

⇒ 16.0 cm/s2

what was the acceleration of the 4 kg cart?

⇒ 8.1 cm/s2

what was the acceleration of the 6 kg cart?

⇒ 5.3 cm/s2

resonant frequency