In source conversion we can simplify circuit by shorting resistor in case of resistor and current source are serially connected and open resistor in case of voltage source and resistance are parallel y connected. But in case of mesh analysis how I calculate the voltage drop in resistor if the resistor and current source is serially connected? do I short the resistance like we do in source conversion or just multiply the current source value with resistance to calculate voltage drop? e.g: mesh analysis in loop 1 where 4 amp current and R4 resistor are serially connected.
You might want to try superposition.
Short all the voltage sources and set them to 0v. Open all the current sources and set them to 0A.
Then one at a time, allow each source to excite the circuit of resistors by itself.
Then add all the results algebraically.