The surface charge density of a thin charged disc of radius R is . The value of the electric field at the centre of the disc is 2 ₀ . With respect to the field at the centre, the electric field along the axis at a distance R from the centre of the disc

Step-by-step solution

Electric field intensity at the centre of the disc. ( E = 2 ₀ (given) ) Electric field along the axis at any distance (x ) from the centre of the disc ( E ^ = 2 ₀ (1- x x ² - R ² ) ) From question, ( x = R ) (radius of disc) ( aligned & E^ = 2 ₀ (1- R R²+R² ) &= 2 ₀ ( 2 R-R 2 R ) &= 4 14 E aligned ) ( ) % reduction in the value of electric field (= ( E - 4 14 E ) 100 E = 1000 14 %=70.7 % )