What happens to the frequency of a wave when its wavelength is doubled, assuming the speed remains constant?

Correct Answer: B

Rationale: When the wavelength of a wave is doubled, and the speed of the wave remains constant, the frequency of the wave is halved. This relationship is governed by the equation speed = frequency x wavelength. Therefore, if the wavelength is doubled while the speed remains constant, the frequency must be halved to maintain a constant speed. Choice A is incorrect because frequency and wavelength are inversely proportional when speed is constant. Choice C is incorrect as doubling the wavelength does not result in a doubled frequency. Choice D is incorrect as the relationship between frequency, wavelength, and speed can be determined using the given information.

Correct Answer: A

Rationale: The resulting intensity of the combined wave is determined by the individual intensities of the waves. When two coherent light waves interfere, the amplitudes of the waves add up, and the resulting intensity is proportional to the square of the sum of the individual amplitudes. Therefore, the individual intensities of the waves play a crucial role in determining the resulting intensity of the combined wave. Choices B, C, and D are incorrect. The wavelength of the waves and the distance between the waves do affect interference patterns but not the resulting intensity. The color of the waves is determined by the wavelength and does not directly determine the resulting intensity of the combined wave.

Correct Answer: D

Rationale: Nuclear fission is the correct answer. It is the process in which a large, unstable nucleus splits into two smaller nuclei, releasing neutrons and energy. Alpha decay, beta decay, and gamma decay involve the emission of alpha particles, beta particles, and gamma rays, respectively. These decay processes do not result in the splitting of a nucleus like nuclear fission does.

Correct Answer: D

Rationale: A) Risk of introducing new diseases: Genetic engineering involves manipulating the genetic material of organisms, which can potentially lead to the creation of new diseases or the spread of existing ones in unintended ways. This risk raises ethical concerns about the potential harm to human health and the environment. B) Potential for misuse and discrimination: Genetic engineering technologies can be misused for purposes such as creating biological weapons or enhancing certain traits in individuals, leading to discrimination based on genetic makeup. This raises ethical concerns about fairness, justice, and the potential for societal harm. C) Unforeseen consequences on ecosystems: Genetic engineering can have unintended consequences on ecosystems, such as disrupting natural balances or harming biodiversity. These unforeseen impacts raise ethical concerns about the responsibility of scientists and policymakers to consider the long-term effects of genetic modifications on the environment. Therefore, the correct answer is D because all the options present valid ethical concerns associated with genetic engineering.

Correct Answer: C

Rationale: A) Exon: Exons are the coding regions of a gene that are transcribed into mRNA and eventually translated into proteins. Exons do not regulate gene expression. B) Intron: Introns are non-coding regions of a gene that are removed during RNA processing and do not play a direct role in controlling gene expression. C) Promoter: The promoter is a regulatory region located at the beginning of a gene that initiates the process of transcription by binding transcription factors and RNA polymerase. It plays a crucial role in controlling gene expression. D) Enhancer: Enhancers are regulatory regions that can be located far from the gene they regulate and can increase the transcription of a gene. While enhancers are important for gene expression, the specific region that controls gene expression is the promoter. Therefore, the correct answer is C) Promoter, as it is the regulatory region in a gene that controls its expression by initiating transcription.