Auniformly charged disk with radius r = 40.0 cm and uniform charge density σ = 7.20 ✕ 10−3 c/m2 lies in the xy-plane, with its center at the origin. what is the electric field (in mn/c) due to the charged disk at the following locations? (a) z = 5.00 cm mn/c (b) z = 10.0 cm mn/c (c) z = 50.0 cm mn/c (d) z = 200 cm mn/c

(a) 356.313 MN/C

(b) 307.909 MN/C

(c) 89.078 MN/C

(d) 7.728 MN/C

Explanation:

where;

is Electric field due to location "Z"

K is coloumb's constant = 8.99 X 10⁹ Nm²/C²

is charge density, = 7.20 X 10⁻³ C/m²

R is the radius of the charged disk = 40.0cm

Step 1: calculate the electric field due to location 5.0 cm

= 356.313 MN/C

Step 2: calculate the electric field due to location 10.0 cm

= 307.909 MN/C

Step 3: calculate the electric field due to location 50.0 cm

= 89.078 MN/C

Step 4: calculate the electric field due to location 200.0 cm

= 7.728 MN/C

here we know that ball will drop down by total distance 3.2 m

so here we know that

now using kinematics

now in the same time it will cover horizontal distance of 0.75 m

so speed of the ball will be