
The circuit for studying the V-I characteristics of a p-n junction diode typically includes:
- A variable DC power supply to provide different values of voltage \( V \),
- A p-n junction diode,
- A series resistor to limit the current through the diode, and
- A voltmeter and ammeter to measure the voltage across and the current through the diode, respectively.
Here is a simple diagram: \[ \begin{array}{c} \text{DC Power Supply} \quad \longrightarrow \quad \text{Series Resistor} \quad \longrightarrow \quad \text{P-N Junction Diode} \quad \longrightarrow \quad \text{Ammeter} \quad \longrightarrow \quad \text{Voltmeter} \end{array} \] The current and voltage are varied, and the corresponding V-I characteristics are plotted.
A small bob A of mass m is attached to a massless rigid rod of length 1 m pivoted at point P and kept at an angle of 60° with vertical. At 1 m below P, bob B is kept on a smooth surface. If bob B just manages to complete the circular path of radius R after being hit elastically by A, then radius R is_______ m :