KCET2014PhysicsElectromagnetic Waves
A multi meter reads a voltage of a certain A.C. source as ( 100 ~V ). What is the peak value of voltage of A.C. source ?
Options
- A( 200 ~V )
- B( 100 ~V )
- C( 141.4 ~V )
- D( 400 ~V )
Correct answer
C. ( 141.4 ~V )
Step-by-step solution
The root mean square value of voltage, ( v_ rms ) and the peak voltage, ( v₀ ) of an ac source are related as ( v_ rms = v₀ 2 ) Given, ( v_ rms =100 ~V ) Therefore, ( v₀= 2 v_ r m s =1.44 100=141.4 ~V ) Thus, peak value of voltage of ac source is ( 141.4 ~V ).