Which of the following statements is true about LEDs
High operational voltage
Warm-up time is required
Bandwidth of ligth is 4000 A -7000 A
Fast on-off switching
A tightly wound long solenoid carries a current of 1.5 A. An electron is executing uniform circular motion inside the solenoid with a time period of 75 ns. The number of turns per meter in the solenoid is …………