I am trying to switch a DC motor using an NPN transistor.
When I connect the motor directly to the battery, it works.
I built a traditional transistor switch circuit with potential divider. To switch the transistor on, I use an LDR. It is all balanced and works well with an LED.
After replacing the LED with the DC motor, it did not run. I used a 9V battery.
What surprises me is that when I measure the voltage between the collector and positive terminal, it shows 8.7V. When I connect the DC motor and measure it again, it shows 0V.