*crib sheet can contain anything you wish except answers to questions. **review slides from february 16th are posted on mycourses under content > review. Question 4: what is true about resistors in parallel, req is greater than either r1 or r2. Question 7: circuit consists of 3 identical lamps connected to battery; the battery has some internal resistance. Voltage across resistor = emf - ir. Req = 2/3r; lower than any of the resistors present. Three light bulbs in parallel (one in parallel two in series) More current flowing through more current through r-branch in the parallel (v/req where req is significantly smaller than any. The current increase leads to a smaller voltage available across points a and b (same voltage across c and a+b; icr = V = iab(2r); thus iab, current across points a and b, must decrease) Less power across a-b (i. e. (v_ab)^2/(2r)) than when switch is open so your light bulbs will be dimmer.