Electromagnetic Spectrum
Muhtasari
Radio waves, microwaves, infrared, visible light, ultraviolet, X-rays and gamma rays look like seven different things, but they are one family: the electromagnetic spectrum. They differ only in frequency and wavelength, and they all race through space at the same enormous speed.
In this lesson you will put the regions in order, learn the everyday uses of each, understand the harm that too much of each can do, and use the fact that all electromagnetic waves travel at \(3.0 \times 10^{8}\,\text{m/s}\) in a vacuum. This is one of the most fact-rich and frequently tested topics in the course.
Malengo
- Know the main regions of the electromagnetic spectrum in order of frequency and in order of wavelength
- Know that all electromagnetic waves travel at the same high speed in a vacuum
- Describe typical uses of the different regions of the electromagnetic spectrum including: (a) radio waves; radio and television transmissions, astronomy, radio frequency identification (RFID) (b) m icrowaves; satellite television, mobile phones (cell phones), microwave ovens (c) infrared; electric grills, short range communications such as remote controllers for televisions, intruder alarms, thermal imaging, optical fibres (d) visible light; vision, photography, illumination (e) ultraviolet; security marking, detecting fake bank notes, sterilising water (f) X-rays; medical scanning, security scanners (g) gamma rays; sterilising food and medical equipment, detection of cancer and its treatment
- Describe the harmful effects on people of excessive exposure to electromagnetic radiation, including: (a) microwaves; internal heating of body cells (b) infrared; skin burns (c) ultraviolet; damage to surface cells and eyes, leading to skin cancer and eye conditions (d) X-rays and gamma rays; mutation or damage to cells in the body
- [Supplement] Know that the speed of electromagnetic waves in a vacuum is 3.0 × 108 m / s and is approximately the same in air
Maelezo ya Somo
Inapatikana kwenye programu ya Green Bridge
Pakua programu ya Green Bridge CBT kwenye simu yako au kompyuta yako ili kupata maelezo kamili ya masomo, maswali ya mazoezi, na mengi zaidi.
Tathmini ya Somo
Hongera kwa kukamilisha somo la Electromagnetic Spectrum. Sasa kwa kuwa umechunguza dhana na mawazo muhimu, ni wakati wa kuweka ujuzi wako kwa mtihani. Sehemu hii inatoa mazoezi mbalimbali maswali yaliyoundwa ili kuimarisha uelewaji wako na kukusaidia kupima ufahamu wako wa nyenzo.
Utakutana na mchanganyiko wa aina mbalimbali za maswali, ikiwemo maswali ya kuchagua jibu sahihi, maswali ya majibu mafupi, na maswali ya insha. Kila swali limebuniwa kwa umakini ili kupima vipengele tofauti vya maarifa yako na ujuzi wa kufikiri kwa makini.
Tumia sehemu hii ya tathmini kama fursa ya kuimarisha uelewa wako wa mada na kubaini maeneo yoyote ambapo unaweza kuhitaji kusoma zaidi. Usikatishwe tamaa na changamoto zozote utakazokutana nazo; badala yake, zitazame kama fursa za kukua na kuboresha.
- Which region has the highest frequency? A. radio waves B. infrared C. visible light D. gamma rays Answer: D
- The speed of all electromagnetic waves in a vacuum is about: A. 330 m/s B. 1500 m/s C. 3.0 x 10^8 m/s D. 3.0 x 10^6 m/s Answer: C
- Which region is used in television remote controls? A. ultraviolet B. infrared C. X-rays D. gamma rays Answer: B
- Excessive ultraviolet radiation can cause: A. skin cancer and eye damage B. only skin burns C. internal heating of cells D. no harm Answer: A
- An EM wave of frequency 1.0 x 10^9 Hz has a wavelength in a vacuum of: A. 0.30 m B. 3.0 m C. 3.0 x 10^17 m D. 0.030 m Answer: A
Inapatikana kwenye programu ya Green Bridge
Pakua programu ya Green Bridge CBT kwenye simu yako au kompyuta yako ili kupata maelezo kamili ya masomo, maswali ya mazoezi, na mengi zaidi.
Inapatikana kwenye programu ya Green Bridge
Pakua programu ya Green Bridge CBT kwenye simu yako au kompyuta yako ili kupata maelezo kamili ya masomo, maswali ya mazoezi, na mengi zaidi.
Vitabu Vinavyopendekezwa
Fanya Mazoezi ya Maswali ya Majaribio
Ungependa kufanya mazoezi ya maswali ya majaribio kuhusu Electromagnetic Spectrum? Pakua programu ya Green Bridge CBT ili kupata maswali ya majaribio na tathmini kamili za mazoezi kuhusu mada hii.
Pakua Programu Kwenye Google Playstore
Kila kitu unachohitaji ili kufaulu katika JAMB, WAEC & NECO.
