Question

2. If the wavelength of a light in a vacuum is 5.12 * 10m, and the frequency of the light is 5.86 * 1015Hz, what is its velocity? (3 marks) 3. If a wave travels with a velocity of 10m/s, and its frequency is 20Hz, what is its wavelength? (3 marks) 4. As shown in the diagram, what is the frequency of the wave? (3 marks) v=2m/s 2 1 -2 5. If a man's face is 30.0 cm in front of a concave shaving mirror creating an upright image 1.50 times as large the object, what is the mirror's focal length? (5 marks) 6. Red light has a frequency of 4.0 x 10E14 Hz. (a) Find the speed of light in a vacuum if its wavelength is 7.5 x 10E-7m? (3 marks) (b) As the red light above enters glass its wavelength changes to 5,8 x 10E-7 m, but its frequency remains constant. What is the speed of red light in this glass? (3 marks) MacBook Air go DOO F2 F3 ODD F4 F5 F6 F7

Answer 1

2) Coarelentah X2 512x107m 5.86 x 1015 H2 frequency velocity xxn 5.12 x 5.86 x 1015 x107 N 109 m/s 3 x 10 m/s Va 10 mis 37 velocity frequency Az fa 20 0-5 m N wareentgh tok 10 20 a = 47 According to the diagram care-lentgh P-(-2) = 4 m and velocity 2 mls 30, frequency 0.5 H2 2 2 Y dla -> 30cm 30x1.5 cm CS Scanned with CamScanner

object and 1 7.5 x 1007 as immage is 1.5 times larger than the is also 1.5 The immage distance times of object distance so, 1.5 ou a 15x30 cm 45 cm -30 cm object distance distance let focus 는 f .3 + 2 So fa -90 focal 14 Hz + th s's 30 90 cm 90 cm So, lentgh is +7 6) a) frequency fa 4x104 =xxf. 7.5xG x 16t 3x10 velocity m/s CS Scanned with CamScanner

14 Hz 5.8 x 1607 n. by Inside the glass f = 4410 and wavelentah 2 = oxf So, velocity frequency mis 5.8 x 4 x 107 8 mis 2.32 x 10 mils CS Scanned with CamScanner