Question

The horizontal deflection plates in a cathode ray tube are 30 mm long and 5 mm apart. The centre of these plates is 60 cm from the screen, accelerating plate voltage is 3000 V. The deflection sensitivity is _______ mm/V.

• A. 0.6

Answer 1

The correct option is A 0.6
Deflection sensitivity,
$S=\frac{L{l}_d}{2d{V}_a}$

Given, $L=60cm$
$l_d=30mm$
$d=5mm$
$V_a=3000V$

$=\frac{\left(0.60\right)\left(0.03\right)}{2\times 0.005\times 3000}m/V=\frac{\left(0.60\right)\left(0.03\right)}{2\times 0.005\times 3}mm/V$

= 0.6 mm/V