Please answer 16,17,18,19,20 and fully explaination. Please see the table belown to know about the result.

16. The small spheres at S and T have charges of +8.0 JC and -8.0 JC, respectively. Find the net electric field at point P -Z 3.0 E cm 4.0 cm 17. Using monochromatic light, an interference pattern is generated on a screen 50.0 cm away from a single slit. The width of the slit is 12 um. The third dark fringe is 6.0 cm from the centre of the central maximum. What is the wavelength of the light used in nanometres? 18. An interference pattern is generated on a screen 6.8 m away from a single slit. Monochromatic light with a wavelength of 445 nm is used. A second- order minima (i.e. second dark fringe from the middle of the central maximum) occurs at 48 cm. What is the width of the slit? 19. A student performing Young's Experiment measures a distance of 4.0 cm between the first and sixth nodal line on a screen that is located 2.4 m from the slits. If laser light with a wavelength of 630 nm is used, then what is the separation of the slits. 20. A camera lens (n = 1.51) is coated with a thin film with a refractive index of 1.25. What should be the minimum thickness of the film to minimize reflected light with a wavelength of 570 nm? ANSWERS TO REVIEW 1 39 m/s [ 63 to the ground] 11 5.9 x 103 m/s 2 13 m/s [N 18 W] 12 17 cm 3 2.3 x 102 m 13 8.7 x 103 m/s 4 17 m/s [310 up from ground] 14 6.4 x 10-13 C 5 0.42 m/s 15 2.3 h 6 0.43 m/s? [up] 16 6.7 x 10' N/C [E 70'S] 7 1.6 m/s 17 480 nm 8 1.4 x 103 N 18 1.3 x 105 m 9 39% is lost 19 1.9 x 104m 10 2.2 m 20 1.1 x 10 m