The dielectric material of thickness[K=1.75] 5mm is completely introduced in between the circular plate of capacitor having radius 3cm. The charge on each plate is 80µC. Find electric field between the plate of the capacitor

From a distance of 10 cm, a proton is projected with a speed of v=4.0106 m/s directly at a large, positively charged plate whose charge density is =2.0105 C/m2. (See below.) (a) Does the proton reach the plate? (b) If not, how far from the plate does it turn around?

Check Your Understanding What is the electric field due to a single point particle?

An election enters a region between two large parallel plates made of aluminum separated by a distance of 2.0 cm and kept at a potential difference of 200 V. The electron enters through a small hole in the negative plate and moves toward the positive plate. At the time the electron is near the negative plate, its speed is 4.0103 m/s. Assume the electric field between the plates to be uniform, and find the speed of electron at (a) 0.10 cm, (b) 0.50 cm, (c) 1.0 cm, and (d) 1.5 cm from the negative plate, and (e) immediately before it hits the positive plate.