Synthesis

The test charge ( blue color ) moves under the effect of the field of
three immobile charges, that are situated in points A, B, C. the trajectory is
highlighted as it moves.

Activities

**Question 1:** Using the diagram, can you find whether charges
A, B, C are positive or negative?

**Q****uestion 2:** Can you explain the direction and
sign of the force's vector at the end of the motion? Can you predict the
following steps of the motion? *(confirm
your answer with the velocity's vector) *

**Exercise:** Can you calculate the rate of every charge? Given
that q=10^{-9}C*( hint: use the
"<step" and "step>" buttons and observe the motion
in detail) *