Electronics Practice Problems with Step-by-Step Solutions

Six units, graded, with step-by-step solutions

59 problems across the six units that open most circuit theory and electronics courses. Every number was worked out and checked; after you submit, each problem shows the answer, a step-by-step solution and a link to the calculator that does the same sum.

• EX1Ohm's law and powerV = IR, power and ratings in 10 problems10 problems · not tried yet
• EX2Series and parallelEquivalent resistance and mixed networks, 10 problems10 problems · not tried yet
• EX3Voltage dividerOutput voltage, loading and ADC scaling, 9 problems9 problems · not tried yet
• EX4RC circuitsTime constant, charging and cutoff, 10 problems10 problems · not tried yet
• EX5DiodesRectifiers, ripple, zeners and LEDs, 10 problems10 problems · not tried yet
• EX6BJT basicsBeta, switches, bias and gain, 10 problems10 problems · not tried yet

How it works

• Pick a unit, answer the problems, then press Submit and grade. Blank answers count as wrong.
• Type numeric answers in the unit shown. Rounding differences up to ±2% count as correct.
• Your best and latest score for each unit appear in this list. They are stored only in this browser.
• Read the solutions to the ones you missed, then use Start over to try the unit again.

Which order to work in

The units follow the order most courses teach them, and each one uses the ones before it. Ohm's law and series and parallel sit under every other problem, and the voltage divider is the first place they combine. RC circuits are the first unit with time in them, and students who are rusty with exponentials tend to stall there. The diode and BJT units come back to the earlier sums once the part is replaced by a fixed voltage drop or a current gain, so if BJT bias problems keep going wrong, a second pass through the divider unit is often the quickest fix.

Using it to revise for an exam

• Work each problem on paper first, with units written at every step, and type only the final answer. That sticks far better than reading the solution alongside.
• For each miss, find the step where your working split from the solution. The mistakes usually fall into a few kinds, such as mixing mA and A or adding parallel parts as if they were in series.
• Use the calculator link under each solution to change one value, predict how the answer should move when a resistor or voltage doubles, and check.
• Come back a few days later and use Start over; the list keeps both your best and your latest score so you can see what stuck.

Clear scores