# Charge Q Is a Negative and Moving Through an Electric Field Problem

PPayment for the chemistry work and below physics question

Charge q is moving through an electric field. If the charge is negative and moves from A to B:

a) is (delta)V positive or negative?

b) is (delta) U positive or negative?

c) is electric potential energy added to the charge?

Explain please! Charge q is moving through an electric field. If the charge is negative and moves from A to B:

a) is (delta)V positive or negative?

(delta)V is negative.

Explanation: Assuming that the lines shown are electric field files, so the field’s direction is from A to B.

As we know the direction of electric field is from positive potential (higher potential) to negative

potential (lower potential. Comparing both, the potential at A will be higher than potential at B.

So ΔV=Vb-Va= negative

Here, please note the reason for the negative charge to move in the less potential side may be due to

some external force acting on the charge or initial acceleration of the charge before entering to the

field. Without any external force the negative charge, should move in opposite direction of field.

b) is (delta) U positive or negative?

(delta)U is positive.

Explanation: ΔU = qΔV, here, from part a), ΔV is negative and it is given that q is negative, so the ΔU will

be positive.

c) is electric potential energy added to the charge?

Yes, the electric potential energy is added to the charge.

Explanation: Since the negative charge is moving in the direction of low potential (in the direction of

electric field), the potential energy will increase (as shown in part b). The increase in potential energy is

by some external force. So the electric potential energy is added to the charge. Negative charge requires

extra energy to move in the direction of field since there will be repulsive force due to the negative

potential difference.

B

А

E

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