Nokea
What is the relationship between the speed of a wave, its frequency, and wavelength in a given medium?
- A. Speed = Frequency Wavelength
- B. Speed = Frequency · Wavelength
- C. Speed = Frequency + Wavelength
- D. Speed = Frequency - Wavelength
Correct Answer: A
Rationale: The speed of a wave in a given medium is determined by the product of its frequency and wavelength. This relationship is described by the formula: Speed = Frequency Wavelength. When a wave travels through a medium, the speed at which it propagates is directly proportional to both its frequency and wavelength. Therefore, to calculate the speed of the wave, you multiply the frequency of the wave by its wavelength. Choices B, C, and D are incorrect because speed is not determined by division, addition, or subtraction of frequency and wavelength; instead, it is determined by their multiplication in the given medium.
You may also like to solve these questions
What is the measure of the total amount of space occupied by an object?
- A. Mass
- B. Density
- C. Weight
- D. Volume
Correct Answer: D
Rationale: Volume is the measure of the total amount of space occupied by an object. Mass refers to the amount of matter in an object, density is the mass per unit volume, and weight is the force of gravity acting on an object. When determining the space occupied by an object, volume is the appropriate measurement to consider. Therefore, the correct answer is D. Choices A, B, and C are incorrect as they do not directly indicate the total amount of space occupied by an object. Mass, density, and weight are relevant in different contexts and measurements compared to volume.
What is the main purpose of biological classification?
- A. To create a rigid and unchanging system for labeling organisms
- B. To understand the diversity and interconnectedness of life
- C. To simplify nature into neat and tidy categories
- D. To assign organisms to specific ecological niches
Correct Answer: B
Rationale: Biological classification, also known as taxonomy, is the science of categorizing and organizing living organisms based on shared characteristics. The main purpose of biological classification is not to create a rigid and unchanging system (option A) or to simplify nature into neat and tidy categories (option C). Instead, it aims to help us understand the diversity of life on Earth and how different organisms are related to each other. By classifying organisms into groups based on their evolutionary relationships, we can gain insights into the interconnectedness of life and better appreciate the complexity and beauty of the natural world. Assigning organisms to specific ecological niches (option D) is more related to ecological studies rather than biological classification.
Balance the following redox reaction in acidic solution: Iâ» (aq) + Crâ‚‚O₇²â» (aq) -> Iâ‚‚ (aq) + Cr³âº (aq). Identify the oxidizing agent and reducing agent.
- A. Iâ» is oxidized, Crâ‚‚O₇²â» is reduced
- B. Iâ» is reduced, Crâ‚‚O₇²â» is oxidized
- C. Both Iâ» and Crâ‚‚O₇²â» are oxidized
- D. Both Iâ» and Crâ‚‚O₇²â» are reduced
Correct Answer: B
Rationale: In the given redox reaction, Iâ» is gaining electrons to form Iâ‚‚, which means Iâ» is being reduced (undergoing reduction). On the other hand, Crâ‚‚O₇²â» is losing electrons to form Cr³âº, indicating that Crâ‚‚O₇²â» is being oxidized (undergoing oxidation). Therefore, Iâ» is the reducing agent and Crâ‚‚O₇²â» is the oxidizing agent. Choice A is incorrect because Iâ» is being reduced, not oxidized. Choice C is incorrect as both species cannot be oxidized in the same reaction. Choice D is incorrect as both species cannot be reduced in the same reaction.
What is the shape of the DNA molecule?
- A. Linear
- B. Circular
- C. Double helix
- D. Straight chain
Correct Answer: C
Rationale: The correct answer is C: Double helix. The shape of the DNA molecule is a double helix, a structure first described by James Watson and Francis Crick in 1953. This shape consists of two strands twisted around each other in a spiral. The double helix structure allows DNA to be compactly stored within the cell nucleus and provides stability to the molecule. Options (A) Linear, (B) Circular, and (D) Straight chain are incorrect as they do not accurately represent the shape of the DNA molecule. DNA is not linear but rather forms a twisted double helix; it is not circular like a ring but has a spiral structure, and it is not a straight chain but a twisted ladder-like structure.
What is the term for the process of a gas changing directly into a solid?
- A. Condensation
- B. Deposition
- C. Sublimation
- D. Evaporation
Correct Answer: B
Rationale: The correct term for the process of a gas changing directly into a solid is deposition. During deposition, gas particles lose energy and transition directly into the solid state without passing through the liquid phase. Sublimation, on the other hand, is the process in which a solid changes directly into a gas without going through the liquid phase. Condensation is the process where gas changes into a liquid state. Evaporation, on the contrary, is the conversion of a liquid to a gas. Therefore, the correct answer is B, deposition.