1. The problem statement, all variables and given/known data Consider a potential divider circuit with an LDR and a fixed resistor. The circuit is powered by a battery which has an emf of 45V with negligible internal resistance. (a) Describe and sketch a circuit that could use a voltmeter or an ammeter to act as a light meter such that an increase in light intensity will cause an increase in the light meter reading. (b) The light intensity can cause a variation in the resistance of the LDR from 250-1500 Ohms. If the available options for the fixed resistor are 750 or 1000 Ohms. Use calculations to show which fixed resistor will give the biggest scale change on the light meter. (c) How would you find the value for the fixed resistor that would give the largest possible scale change on the light meter. 2. Relevant equations VT/(R1+R2) = Vo/R2 where R1 is the LDR, R2 is the fixed resistor, VT is the emf (45V), Vo is the potential difference across R2. 3. The attempt at a solution (a) If choosing the ammeter as light meter it simply goes in series with the rest of the components. If choosing voltmeter must go across R2 in order to increase with increasing light intensity. (b) From my calculations the 750 ohm resistor would give a voltage range of 18.75V across R2 when the LDR varies from 250-1500. The 1000 ohm resistor would give a range of 18V so the 750 ohm resistor is the best choice. (c) I have no idea with this part! I can randomly select resistances and calculate the range they would give but I have no idea how you find the exact resistance that gives the largest range? Thanks for any help given.