Noob here. If I plug in my DC motor into 5V and GRD, it will run. However, plugging the DC motor into GRD and an Arduino pin and then using digitalWrite(dc_pin, HIGH), the motor will not spin. It will spin if I set up the DC motor with a transistor and control the transistor with an Arduino pin. Why is this? Is the Arduino pin not giving out 5V when set to high?