What should be the power of the voltage supply that we will use in the acceleration region?

Consider what happens when a person moves around in dry conditions. The rubbing of motion leads to static electric charge building up on the body. Assume the capacitance of the human body to be about 155 pF. a) How much charge would have to build up on a body to generate a potential difference of 10 kV? b) A particular cell phone can have its circuits destroyed if exposed to an electric shock containing 300 u.J of energy. What voltage does that correspond to if the shock is coming from a human body?

Physics Question: Please take a look at this question and answer the following! Thank you so much!

A parallel plate capacitor used in a flash for a camera must be able to store 16.0 J of energy when connected to 309 V. (Most electronic flashes actually use a 1.50- to 6.00-V battery, but increase the effective voltage using a dc–dc inverter.)     What should be the capacitance of this capacitor?

With the switch open, the potential difference across the capacitor shown is 10.0 V. After the switch is closed, how long will it take for the potential difference across the capacitor to decrease to 5.0 V?