Final answer:
The statement on wave-particle duality for macroscopic objects is false as the concept applies to quantum scales, and the statement about the observed frequency becoming infinite at the speed of sound is also b. false.
Step-by-step explanation:
To assess the truth value of a statement, one often looks at empirical evidence or logical coherence. For example, the statement about wave-particle duality existing for macroscopic objects is false; wave-particle duality is a concept in quantum mechanics that applies to microscopic particles such as electrons, not to macroscopic objects. Similarly, the idea that the observed frequency becomes infinite when the source moves at the speed of sound is also false; if the source is moving at the speed of sound, the wavelengths in front of the source compress, but they do not result in an infinite frequency.
Understanding the true or false nature of statements is key in learning physics, as it helps students differentiate between correct and incorrect concepts, which is essential for building a solid foundation in the subject. Determining the truthfulness of a statement requires analyzing the statement based on scientific principles and empirical evidence.