How does capacitors provide initial high voltage for a motor? While observing the water pump in my house I could see a huge capacitor connected to it.  My father told me that it is to provide a high voltage of 440 V during the start-up process. But, how does a capacitor do that?
From, my high school knowledge I know that a capacitor allows AC current to flow through it.  But, how does it increase the voltage at the beginning for the motor to start?  
 A: Certain types of AC motors have no torque at 0 speed because the net torque balances out over a line cycle.  The capacitor unbalances the system so that it has some torque at startup.  Usually there is a switch that disconnects the capacitor once the motor gets to a certain speed.  The reason for disconnecting it once the motor is running is that at normal speed the imbalance caused by the capacitor causes inefficiency.
Not all motors work that way, but this type of motor is fairly common because it's cheap to produce.  Look up something called a shaded pole or startup capacitor for more information.
A: The voltage marked on the capacitor is the maximum voltage that it is rated to work at.
Motors typically have several coils around the rotor. Current goes through these coils to create a magnetic field that interacts with permanent magnets positioned around the shell of the motor. In steady operation the current flips direction just as the field coil reaches the next magnet. At start up the mains frequency is too fast for the initially stationary rotor to move to the next magnet. The capacitor is used to produce a lag in the time it takes to build up the magnetic field in one of the coils in the motor. This introduces an imbalance in the magnetic fields and creates a torque that sets the motor turning.
