2. A solid is rigid and cannot be compressed easily. Reason: Molecules are closely spaced and the intermolecular separation is very small which cannot be reduced further. 3. A solid does not diffuse into another solid easily. Reason: Intermolecular force of attraction is very strong. 4. A solid does not flow and can be stored in a container. Reason: Intermolecular fore of attraction is so strong that molecules do not flow and leave the surface of the solid. 5. A solid on hating usually changes into its liquid state.
To PWM, or not to PWM, That is the Question. Pulse width modulation (PWM) is a fancy term for describing a type of digital signal. Pulse width modulation is used in a variety of applications including sophisticated control circuitry. A common way we use them here at SparkFun is to control dimming of RGB LEDs or to control the direction of a servo motor.
In short, PWM operates like a switch which constantly cycles on and off, thereby regulating the amount of power the fan or pump motor gains. The PWM system that is used for controlling fans and pumps works with the motor, either getting +12V (full power) or 0V (no power). To have a better understanding how this works, take a look at the chart bellow. So, the motor is being fed impulses of power.