Role of Resistor in charging Capacitor

Note while we were charging the capacitor , a resistor was connected in circuit. The resistor determine that how quickly should the capacitor charge .

If a large value of resistor is used in circuit , the capacitor will take more time for charging as compared to a circuit where small , resistor in connected

 

For understanding the resistor role, , we will analyze the voltage signal across the capacitor on a oscilloscope .

Let say we have chosen 1 Kilo resistor , which is connected in a circuit with series in 6 Volts battery and a capacitor.

 

Notice that it have taken a small time for voltage signal across capacitor , from moving between zero to six(shown in red box above), indicating that capacitor has completely charged .

Now lets increase the resistor value and see the effect. Now we have chosen the 10 k resistor . Notice the time taken by capacitor (highlighted in red box) to move from zero volts to 6 volts (charged capacitor)