which phenomenon explains the formation of rainbows in the sky

ATI TEAS 7

TEAS version 7 quizlet science

1. What phenomenon explains the formation of rainbows in the sky?

A. Diffraction
B. Interference
C. Refraction and dispersion of sunlight by water droplets
D. Reflection from clouds

Correct answer: C

Rationale: Rainbows are formed due to the refraction and dispersion of sunlight by water droplets in the atmosphere. When sunlight enters a water droplet, it is refracted, then internally reflected, and finally refracted again as it exits the droplet. This dispersion of light into its component colors creates the beautiful rainbow we see in the sky. Choice A, diffraction, involves bending of light around obstacles or through narrow openings, not the splitting of light into colors as seen in rainbows. Choice B, interference, refers to the phenomenon where two or more light waves overlap and interact, producing a pattern of light and dark bands, which is not the case with rainbows. Choice D, reflection from clouds, does not accurately describe the process involved in the formation of rainbows through refraction and dispersion of light by water droplets.

2. The acceleration of a falling object due to gravity has been proven to be 9.8 m/s^2. A scientist drops a cactus four times and measures the acceleration with an accelerometer and gets the following results: 9.79 m/s^2, 9.81 m/s^2, 9.80 m/s^2, and 9.78 m/s^2. Which of the following accurately describes the measurements?

A. They're both accurate and precise.
B. They're accurate but not precise.
C. They're precise but not accurate.
D. They're neither accurate nor precise.

Correct answer: A

Rationale: The measurements are close to the true value of 9.8 m/s^2 and are also close to each other, indicating both accuracy and precision. Accuracy refers to how close a measurement is to the true value, while precision refers to how close repeated measurements are to each other. In this case, the measurements are accurate because they are close to the accepted value of 9.8 m/s^2, and they are precise because they are clustered closely around each other. Therefore, choice A, 'They're both accurate and precise,' is the correct answer. Choice B is incorrect because the measurements are precise as they are close to each other, but they are also accurate as they are close to the true value. Choice C is incorrect because the measurements are accurate as they are close to the true value, and choice D is incorrect because the measurements exhibit both accuracy and precision in this scenario.

3. What information can be obtained from the mass number of an element?

A. The number of protons in the nucleus
B. The total number of protons and neutrons
C. The number of electrons in the valence shell
D. The element's chemical reactivity

Correct answer: B

Rationale: The mass number of an element represents the total number of protons and neutrons in the nucleus. This information is crucial for determining the atomic mass of the element and understanding its stability and isotopes. The number of protons in the nucleus (option A) is represented by the atomic number, not the mass number. The number of electrons in the valence shell (option C) is related to the element's position in the periodic table and its chemical properties, but it is not directly determined by the mass number. The element's chemical reactivity (option D) is influenced by the number and arrangement of electrons in the atom's energy levels, not by the mass number.

4. What is the basic unit of communication in the nervous system?

A. Neuron
B. Astrocyte
C. Neurotransmitter
D. Synapse

Correct answer: A

Rationale: A neuron is the basic unit of communication in the nervous system. Neurons are specialized cells responsible for transmitting information through electrical and chemical signals. Astrocytes are a type of glial cell that provide support and nourishment to neurons but do not participate in signal transmission. Neurotransmitters are chemicals that facilitate signal transmission between neurons, and synapses are the specific junctions where these signals are transmitted. Therefore, the correct answer is 'A: Neuron' as it is the primary cell involved in transmitting information in the nervous system.

5. What effect does doubling the net force applied to an object have on its acceleration, assuming mass remains constant?

A. Acceleration doubles
B. Acceleration is halved
C. Acceleration remains the same
D. Acceleration quadruples

Correct answer: A

Rationale: According to Newton's second law of motion, acceleration is directly proportional to the net force applied to an object when mass is constant. Therefore, if the net force is doubled, the acceleration of the object will also double. This relationship is expressed by the formula F=ma, where F is the net force, m is the mass, and a is the acceleration. When mass is constant, doubling the force applied will result in a proportional doubling of acceleration. Choices B, C, and D are incorrect because doubling the net force does not halve, maintain, or quadruple the acceleration; it directly and proportionally increases the acceleration.