Answer Happy

A variable DC power supply and an ammeter is connected to aresistor circuit as shown above. Two resistors are known, but R1 isunknown. In order to calculate the resistance of R1 voltage andcurrent data are recorded as the power supply voltage is increasedfrom 2 V to 10 V. A table containing the data is shown below.
1. Plot the data using Excel or another data analysis programthat can provide you with a curve fit. Be sure to label axes andperform a curve fit before taking a screen shot.
Calculate the total resistance of the circuit from your curvefit results.
3. Calculate the resistance of R1.
The power supply is now fixed at 12 V and one of the resistorsis replaced by a capacitor as shown below.
4. Calculate the current in the circuit immediately after theswitch is closed.
5. Calculate the current in the circuit a long time after theswitch has been closed.
6. Sketch the circuit, clearly identify junctions and loops youuse. Also include clearly labeled equations for each junction andloop you use. (Don’t list all possibilities, only the ones you aregoing to use for the next part!)
7. Write a differential equation describing the circuit when theswitch is closed in terms of charge. Use VB, R1, R2, C, and Qrather than numerical values and clearly show its derivation fromyour junction and loop equations.
DC Power Supply A www R₁ R₂: R = 50 Ω R, = 50 Ω :
Potential Difference (V) Current (mA) 2 40 4 55 6 97 8 138 10 155
12 V DC Power Supply A R₁ R₂ = 50 52 4 nF