Indicate whether each statement is true or false. If you think the statement is false, rewrite it to make it true. 19. Radio waves go through more cycles per second than X-rays. (9.1, 10.4) 20. Light waves with higher frequencies have longer wavelengths, and light waves with lower frequencies have shorter wavelengths. (9.1) 21. In a ripple tank, a decrease in the frequency of the two vibrating sources causes an increase in the number of nodal lines. (9.3) 22. When two light waves from the same source meet after a path difference of 2.5 wavelengths, they interfere destructively. (9.3) ku 23. The wave model of light cannot explain all wave properties of light. (9.4)24. When light travels from air to glass, the wave theory predicts that the light will slow down but Newtonian particle theory predicts that the light will speed up. (9.4) KAU 25. When a Young's double-slit apparatus is operated in air and then submerged in water, the fringe pattern becomes less spread out. (9.5) 26. Together, Fresnel's and Huygens' principles explain the rectilinear propagation of light and diffraction effects. (9.5) 27. Increasing the width of the slit in a single-slit apparatus causes the distance between adjacent dark fringes to decrease. (10.2) kru 28. For a diffraction grating, the angular separation of the maxima is generally small because the slit spacing is so small. (10.3) 29. Polaroid is used in sunglasses to protect your eyes from glare. (10.5) kru