how is power related to work and time

ATI TEAS 7

TEAS 7 practice test free science

1. How is power related to work and time?

A. Power = Work ÷ Time
B. Power = Work × Time
C. Power = Work + Time
D. Power = Work - Time

Correct answer: A

Rationale: Power is defined as the rate at which work is done or the amount of work done per unit of time. The correct formula to relate power, work, and time is Power = Work ÷ Time. This formula shows that power is calculated by dividing the amount of work done by the time taken to do that work, indicating the rate at which work is being done. Choice B (Power = Work × Time) is incorrect because multiplying work and time does not yield a measure of power. Choice C (Power = Work + Time) is incorrect as adding work and time does not define power. Choice D (Power = Work - Time) is also incorrect because subtracting work and time does not relate to the concept of power.

2. What is the fundamental unit of the nervous system?

A. Neuron
B. Nerve
C. Ganglion
D. Neuroglia

Correct answer: A

Rationale: The correct answer is A: Neuron. Neurons are the fundamental building blocks of the nervous system. These specialized cells play a crucial role in transmitting information through electrical and chemical signals. While nerves are comprised of bundles of neurons and ganglia consist of clusters of nerve cell bodies located outside the central nervous system, neuroglia serve as support cells for neurons. Neurons are specifically responsible for processing and transmitting information within the nervous system, making them the essential unit of this complex system. Choices B, C, and D are incorrect as nerves are bundles of neurons, ganglia are clusters of nerve cell bodies outside the central nervous system, and neuroglia are support cells for neurons, not the fundamental units responsible for information processing and transmission.

3. Which layer of the skin is responsible for new skin cell production?

A. Stratum corneum
B. Stratum basale
C. Stratum granulosum
D. Stratum spinosum

Correct answer: B

Rationale: The correct answer is B, Stratum basale. The stratum basale, also known as the basal layer or stratum germinativum, is the deepest layer of the epidermis and is responsible for new skin cell production through cell division. It contains basal cells that continuously divide to produce new keratinocytes, which move up through the layers of the epidermis. Choice A, Stratum corneum, is the outermost layer of the epidermis consisting of dead cells filled with keratin. It serves a protective function but is not involved in new skin cell production. Choice C, Stratum granulosum, is a layer of the epidermis where keratinocytes undergo changes in their structure and composition. It is involved in the process of keratinization but not in new skin cell production. Choice D, Stratum spinosum, is a layer of the epidermis where cells become interconnected by desmosomes. While it plays a role in providing strength and support to the epidermis, it is not primarily responsible for new skin cell production.

4. Based on the passage, which of the following is the most logical conclusion?

A. The professor will offer another extra credit project later in the semester.
B. Students who choose two extra-credit options will be given double the extra credit.
C. Students who choose the third option will receive one quarter of the offered extra credit.
D. Students are most likely to earn maximum extra credit by choosing the first option.

Correct answer: D

Rationale: Based on the passage, the most logical conclusion is that students are most likely to earn the maximum extra credit by choosing the first option. The first option provides an extra credit project worth 150% of the point value of the essay exam, giving students more than enough chance to make up the difference and raise their overall score. The second and third options also offer the same 150% extra credit, but they involve more subjective scoring or group work, respectively, which may not ensure maximum extra credit. Therefore, choosing the first option is the best way for students to earn the most extra credit.

5. What is the acceleration of an object moving at a constant speed of 20 m/s if it comes to a complete stop within 5 seconds?

A. 0 m/s² (no acceleration)
B. 4 m/s²
C. -4 m/s²
D. Insufficient information

Correct answer: C

Rationale: To find the acceleration, we use the formula: acceleration = (final velocity - initial velocity) / time. Given that the final velocity is 0 m/s (as the object stops), the initial velocity is 20 m/s, and the time taken is 5 seconds. Substituting these values into the formula, we get acceleration = (0 m/s - 20 m/s) / 5 s = -20 m/s / 5 s = -4 m/s². Therefore, the acceleration is -4 m/s², indicating that the object decelerated at a rate of 4 m/s² to come to a complete stop. Choice A is incorrect because the object does experience acceleration as it changes its speed from 20 m/s to 0 m/s. Choice B is incorrect as it represents acceleration in the wrong direction, considering the object is decelerating. Choice D is incorrect as there is sufficient information provided to calculate the acceleration based on the given data.