TEAS 7 science quizlet

Correct Answer: C

Rationale: Refraction occurs due to a change in wave speed when waves enter a new medium. As waves travel from one medium to another, their speed changes, causing them to bend. This change in speed is responsible for the bending of waves during refraction. It is not the change in wavelength or frequency that causes refraction, but rather the change in speed as waves move through different mediums. Therefore, the correct answer is the change in wave speed (Choice C). Choices A and B are incorrect as refraction is not primarily influenced by changes in wavelength or frequency, but by changes in wave speed. Choice D is also incorrect as there is a specific principle, which is the change in wave speed, behind the phenomenon of refraction.

Correct Answer: B

Rationale: Heat and temperature are distinct concepts. Heat is a form of energy that transfers from a higher temperature object to a lower temperature object, while temperature represents the average kinetic energy of particles in a substance. Heat is quantified in units like Joules or calories, whereas temperature is typically gauged in degrees Celsius or Fahrenheit. Therefore, choice B correctly distinguishes between heat and temperature, making it the correct answer. Choices A, C, and D are incorrect because they do not accurately define the difference between heat and temperature. Choice A erroneously suggests they are the same, choice C confuses the direction of heat and temperature flow, and choice D provides inaccurate units for measuring heat and temperature.

Correct Answer: A

Rationale: 1. Boiling point elevation: When a solute is added to a solvent, it raises the boiling point of the solution compared to the pure solvent. This phenomenon is known as boiling point elevation. 2. Van't Hoff factor: The extent of boiling point elevation depends on the number of particles the solute dissociates into in the solution. NaCl dissociates into two ions (Na+ and Cl-) in water, while glucose does not dissociate into ions. Therefore, NaCl has a higher Van't Hoff factor than glucose. 3. Colligative properties: Boiling point elevation is a colligative property, meaning it depends on the concentration of the solute particles, not the identity of the solute. Since both NaCl and glucose are 1 M solutions, the NaCl solution will have a higher boiling point due to its higher Van't Hoff factor. 4. Conclusion: The NaCl solution

Correct Answer: C

Rationale: When there is no external force acting upon an object, the law of conservation of momentum dictates that the momentum of the object remains constant. This means that the momentum does not increase or decrease; it stays the same. Choice A is incorrect because momentum does not increase. Choice B is incorrect because momentum does not decrease. Choice D is incorrect as momentum does not become zero; it remains constant as per the conservation law. Therefore, the correct answer is C, as the object's momentum is unchanged in the absence of external forces.

Correct Answer: B

Rationale: The correct answer is 'Focal length.' Focal length is the term used to describe the point where parallel rays of light converge or appear to diverge after passing through a lens or reflecting off a mirror. It is a critical parameter in optics that determines the magnification and image formation in optical systems. Aperture refers to the opening through which light enters a camera or telescope, not the convergence point of light rays. Refractive index is a measure of how much light is bent, not the point where rays converge. Lens thickness is the physical dimension of a lens and does not indicate the convergence point of light rays. Therefore, 'Focal length' is the most appropriate choice in this context.