SCMH 1010 UNIT 2 EXAM QUESTIONS ANSWERED CORRECTLY LATEST UPDATE 2026

SCMH 1010 UNIT 2 EXAM QUESTIONS ANSWERED CORRECTLY LATEST UPDATE 2026 The current through a 5 ohm resistor is 0.5 amp. What is the voltage across the resistor? 0.1 V 10 V 2.5 V 0.4 V - Answers 2.5 V The current in a circuit is 0.1 amp and the voltage across it is 15 V. The power being supplied by the source is: 0.01 W 0.6 W 150 W 1.5 W - Answers 1.5 W Maxwell's equations mathematically describe: the relationship between electric fields and charges and magnetic fields and poles. all of these. the relationship between changing electric fields and magnetic fields. the relationship between changing magnetic fields and electric fields. - Answers all of these. One significant difference between matter waves (such as earthquakes and sound waves and water waves) and electromagnetic waves is which of the following? Electromagnetic waves don't have detectable effects. Matter waves happen on larger scales. Electromagnetic waves can travel through nothing at all. Matter waves involve some type of up-and-down motion. - Answers Electromagnetic waves can travel through nothing at all. How fast is a wave moving if it has a wavelength of 2 m and a frequency of 5 Hz? 2.5 m/s 10 m/s 0.1 m/s 0.4 m/s - Answers 10 m/s A long, taut string on a guitar is plucked. The wave that travels down its length is: longitudinal. transverse. reversed. latitudinal. - Answers transverse. The nature of an electromagnetic wave is that: the electric field is parallel to the magnetic field and both are perpendicular to the direction of propagation. the electric and magnetic fields are perpendicular to each other and the electric field is parallel to the direction of propagation. the electric and magnetic fields are parallel to each other and to the direction of propagation. the electric field is perpendicular to the magnetic field and both are perpendicular to the direction of propagation. - Answers the electric field is perpendicular to the magnetic field and both are perpendicular to the direction of propagation. What was one of the original motivations for grouping the elements in columns? They are grouped according to similar chemical behavior. They are grouped according to the order in which they were discovered. They are grouped according to similar masses. They are grouped according to similar sizes. - Answers They are grouped according to similar chemical behavior. The least energetic kind of electromagnetic radiation is which of the following? X-rays Infrared waves Radio waves Microwaves - Answers Radio waves The atomic number of an element best corresponds to which of the following? The number of neutrons in the nucleus of an atom of that element. The number of electrons orbiting the nucleus of an atom of that element. The mass of an atom of that element. The number of protons in the nucleus of an atom of that element. - Answers The number of protons in the nucleus of an atom of that element. One significant difference between matter waves (such as earthquakes and sound waves and water waves) and electromagnetic waves is which of the following? a) Matter waves happen on larger scales. b) Electromagnetic waves don't have detectable effects. c) Electromagnetic waves can travel through nothing at all. d) Matter waves involve some type of up-and-down motion. - Answers c) Electromagnetic waves can travel through nothing at all. A wave having a frequency of 10 Hz means which of the following is occurring? a) 10 waves are simultaneously oscillating up and down. b) 1 wave goes up and down 10 times every second. c) Over a distance of 10 m, a wave oscillations up and down 10 times. d) 10 seconds goes by between waves. - Answers b) 1 wave goes up and down 10 times every second. How fast is a wave moving if it has a wavelength of 4.0 m and a frequency of 4 Hz? a) 8 m/s b) 1 m/s c) 16 m/s d) 0 m/s - Answers c) 16 m/s A long, taut string on a guitar is plucked. The wave that travels down its length is: a) latitudinal. b) longitudinal. c) transverse. d) reversed. - Answers c) transverse. Let's take the speed of sound to be 340 m/s. What would be the length of the pipe in a pipe organ that produces a note with a pitch of 170 Hz? a) 4 m b) 2 m c) 1 m d) 0.5 m - Answers c) 1 m What is the frequency of the lowest pitch the human ear can hear? a) 1000 Hz b) 200 Hz c) 100 Hz d) 20 Hz - Answers d) 20 Hz Which of the following is an observation we can make about pipes in a pipe organ? a) The longest pipes give rise to the highest frequencies. b) The shortest pipes give rise to the smallest frequencies. c) The length of the pipe is inversely proportional to the square of the frequency of the sound it produces. d) The length of the pipe is inversely proportional to the frequency of the sound it produces. - Answers d) The length of the pipe is inversely proportional to the frequency of the sound it produces. When two waves, each with identical frequencies and an amplitude of 4 cm, interact with each other at the same point, which of the following happens? a) Without knowing the timing of the waves, we can't say anything. b) The point experiences a shift of 8 cm upwards. c) The point experiences no shift at all. d) The point experiences a shift of 8 cm downwards. - Answers a) Without knowing the timing of the waves, we can't say anything. An electromagnetic wave cannot arise directly from which of the following? a) An accelerating electric charge. b) An electric charge with a changing speed. c) An electric charge moving at a constant speed that is changing direction. d) A sound wave. - Answers d) A sound wave. Which of the following is the best statement regarding the propagation of light through space? a) Electromagnetic waves seem to travel through a medium known as "ether." b) Electromagnetic waves seem to travel through a complete vacuum. c) Electromagnetic waves seem to travel through a universe-wide magnetic field. d) Electromagnetic waves seem to travel through a universe-wide electric field. - Answers b) Electromagnetic waves seem to travel through a complete vacuum. The nature of an electromagnetic wave is that: a) the electric field is parallel to the magnetic field and both are perpendicular to the direction of propagation. b) the electric field is perpendicular to the magnetic field and both are perpendicular to the direction of propagation. c) the electric and magnetic fields are parallel to each other and to the direction of propagation. d) the electric and magnetic fields are perpendicular to each other and the electric field is parallel to the direction of propagation. - Answers b) the electric field is perpendicular to the magnetic field and both are perpendicular to the direction of propagation. Taking the speed of light as being equal to 3 x108 m/s, if an electromagnetic wave has a frequency of 6 x 108 Hz what is its wavelength? a) 0.5 m b) 2 m c) 3 m d) 9 m - Answers a) 0.5 m Looking in the night sky, you notice four different colored stars. Ignoring any influence of the Doppler effect and thus based on the color alone, which star has the hottest surface? a) The light blue one. b) The red one. c) The white one. d) The yellow one. - Answers a) The light blue one. The Doppler Effect is NOT observed where the following occurs: a) The source moves towards or away from the observer. b) The observer moves towards or away from the source. c) Both the observer and the source are moving at the same velocity. d) Both the observer and the source are moving at different velocities. - Answers c) Both the observer and the source are moving at the same velocity. You are driving 15 mph above the speed limit when a police officer aims a radar gun at your car to measure its speed. Your car is moving away from the officer. If the frequency of the radar wave from the gun is 10,525 MHz, what can we say about the frequency of the radar wave reflected off your car? a) It will be higher than 10,525 MHz. b) It will be exactly equal to 10,525 MHz. c) It will be lower than 10,525 MHz. d) It will be much higher than 10,525MHz. - Answers c) It will be lower than 10,525 MHz. Short-wavelength ultraviolet light and gamma rays don't travel very far through the Earth's atmosphere before being absorbed. Based on this, which of the following would you expect to be absorbed by the Earth's atmosphere? a) Infrared rays b) Radio waves c) Microwaves d) X-rays - Answers d) X-rays The type of light with the longest wavelength is known as which of the following? a) Infrared waves b) Microwaves c) Radio Waves d) Visible light - Answers c) Radio Waves Frequency modulation can be described by which of the following? a) A radio wave is allowed to vary in its strength. b) A radio wave is allowed to vary in its speed. c) A radio wave is allowed to vary in its wavelength. d) A radio wave is allowed to vary in its amplitude. - Answers c) A radio wave is allowed to vary in its wavelength. Of the different kinds of cells in the retina, which one is a photoreceptor AND allows us to see colors? a) Rod b) Ganglion c) Cone d) Bipolar - Answers c) Cone The most energetic kind of electromagnetic radiation is which of the following? a) Infrared waves b) Microwaves c) Gamma rays d) X-rays - Answers c) Gamma rays Compounds of what element may be released into the atmosphere upon burning of fossil fuels and lead to formation of acid rain? a) carbon. b) sulfur. c) lead. d) mercury. - Answers b) sulfur. If one were to conduct a cutting experiment like that described by Democritus wherein he envisioned cutting paper into smaller and smaller pieces using the world's sharpest knife, what would the smallest identifiable bit of paper be? a) an atom. b) a molecule. c) a tiny part of an atom. d) an element like hydrogen. - Answers b) a molecule. If you use an electrical current to break down water, you get what two gases? a) hydrogen and oxygen b) carbon and dioxide c) carbon and oxygen d) hydrogen and carbon - Answers a) hydrogen and oxygen How many elements make up most (~99%) of the Earth's mass? a) Two or three. b) Several dozen. c) Six. d) All elements are present in roughly equal amounts. - Answers c) Six. Why will a grain of pollen placed in water will move about erratically? a) In a sufficiently short period of time, the number of water molecules bumping into it from all sides is not the same. b) Currents within the water keep the pollen grain moving about. c) The water molecules in the water are not uniformly distributed and the grain of pollen moves from one region of lower density to another. d) The pollen grain moves from one region of least impurity to another. - Answers a) In a sufficiently short period of time, the number of water molecules bumping into it from all sides is not the same.