In the circuit shown in figure, initially switches s1 and s2 were closed and s3 was open. Now the switches s1 and s2 are opened and s3 is closed. The total heat dissipated by the 10 ω resistor is.

Point charges q1=+2.00μc and q2=−2.00μc are placed at adjacent corners of a square for which the length of each side is 1.50 cm . point a is at the center of the square, and point b is at the empty corner closest to q2. take the electric potential to be zero at a distance far from both charges. part a what is the electric potential at point a due to q1 and q2? express your answer with the appropriate units.