Question

after 23 clock pulses, what will be the state of the leds (on/off)?

Explanation:

Step1: Consider the circuit as a 3 - bit shift register

Assume the initial state of the flip - flops (connected to LEDs) is given as shown. Each clock pulse shifts the data.

Step2: Use binary representation

We can represent the state of the 3 - bit register in binary. The number of clock pulses is 23. We can find the state of the register after 23 clock pulses by looking at the binary value of 23 in a 3 - bit context. 23 in binary is \(10111_2\). But we are dealing with a 3 - bit register, so we consider the remainder when divided by \(2^3=8\). \(23\bmod{8}=7\). The binary representation of 7 is \(111_2\).

Step3: Map binary values to LED states

In the circuit, a 1 corresponds to the LED being ON and 0 to OFF. So for the binary number \(111_2\), LED1 is ON, LED2 is ON, and LED3 is ON.

Answer:

LED1: ON, LED2: ON, LED3: ON