Wish to start blogging about worksheet mistakes.
1. 2ii) The point with the minimum V/I ratio is the point that intersects with the line from the origin that has the steepest gradient. Use a ruler to draw a line touching the curve . The point is 3.4 V and 1.15A which gives R = 2.96 ohm.
2. bii) THE total current from the supply is current through C plus 0.85 A. To obtain current through C ,read off 4.25V from graph to get 1.3 A . Total current 1.3 +0.85= 2.15A
iii) the emf E = V + Ir, where V = 4.25V and I=2.15A and r = 0.8ohm, hence E = 4.25 + 2.15(0.8)= 6.0 V
iv) Energy = VI t = 6630 J
3. Highest power is 5.62 W, hence current is 1.25A.
b) The emf E is constant,hence equating I(R+r) to that from a)
1,25(3.6+r) = 1.6(2.03 + r) , solving for r gives 3.57ohm
Never too late to learn from mistake you make now.
