1. Calculate the RMS values of a sinusoidal alternating voltage applied to the Y plates of a CRO if it gives the following vertical lengths of trace, the Y amplifier control setting for each display being shown after the trace length


(a) 5 cm, 10 V/cm

(b) 9 cm, 50 V/cm

(c) 4 cm, 100 V/cm.

2. The current in a load is displayed on a CRO by passing it through a 1.5 resistor and applying the PD across the resistor to the Y amplifier of the CRO. The peak-to-peak amplitude of the display is 7.5 cm when the amplifier setting is 200 mV/cm. Assuming the current wave-shape to be sinusoidal, calculate the RMS value of the current.