Motors Feb. 16

Understanding motors means more math and abstract thinking. A basic concept about motors is that they measure speed. Speed generates a voltage and current generates a torque. In a motor the power applied is equal to the input voltage times the input current ( Pin = Vin x i in). The output of the power is T (torque) x ω (omega which is believe is a constant). You obtain the torque by multiplying the force produced to cause the rotation by the distance of the bar of the motor.

Inside a motor there is a resistor making a potential difference when the current runs through. The voltage insides the motor is the resistor multiplied by the current plus the Vemf. After passing through the motor the voltage switches from positive to negative (- resistance x current - Vemf). I am still confused about how voltage in a motor so I will further add more information about them in the future.

For our setup, we used three resistors, two potentiometers, a motor, and an adaptor. When my partner and I turned the first potentiometer we were able to see how the axle would start to spin. The motor axle would only spin when we would turn the potentiometer a little past the half way point. At the half way point the motor would stop. It was exciting to control the direction and speed of the motor.

Motor setup

Professor Mur-Miranda asked us to hold on to the wheel, turn the knob on the potentiometer, and look at the graph in the oscillator. The graph showed us how the speed was at zero but there was current still running. I was able to feel the tug of the wheel as I was preventing it from turning. The hands on motor learning helped me understand the make up and function of toys with wheel since the motor with the wheel is very similar to toy remote cars.

Motor with wheel