Nursing Elites

1. The term "barn" is a unit commonly used in nuclear physics to quantify:

• A. Energy (Electron volts are the standard unit for energy in nuclear physics)
• B. Radioactivity
• C. Nuclear cross-section
• D. Half-life

Correct answer: C

Rationale: The term 'barn' is a unit of measurement used in nuclear physics to quantify nuclear cross-section. Nuclear cross-section refers to the measure of the probability of a specific interaction occurring between particles during a nuclear reaction. The term 'barn' was coined based on its relation to the physical size of a nucleus, as it is a small unit of area used to describe the likelihood of a particle interacting with a nucleus. It is not used to quantify energy, radioactivity, or half-life, making options A, B, and D incorrect in this context.

2. Decomposers in an ecosystem play a vital role by:

• A. Photosynthesizing and producing organic matter
• B. Breaking down dead organisms and returning nutrients to the environment
• C. Preying on herbivores and controlling their populations
• D. Fixing nitrogen from the atmosphere and making it available to plants

Correct answer: B

Rationale: Rationale: Decomposers are organisms that break down dead organic matter, such as dead plants and animals, into simpler substances. By doing so, they help to recycle nutrients back into the environment, making them available for other organisms to use. This process is essential for the functioning of ecosystems, as it ensures that nutrients are not lost but instead are continuously cycled through the ecosystem. Photosynthesis (option A) is the process by which plants and some other organisms convert light energy into chemical energy in the form of glucose, and it is not a role of decomposers. Preying on herbivores (option C) is a role typically carried out by predators, not decomposers. Fixing nitrogen from the atmosphere (option D) is a process carried out by nitrogen-fixing bacteria, not decomposers.

3. Which of the following situations represents work being done on an object?

• A. Pushing against a wall without moving it
• B. Carrying a heavy object without lifting it
• C. Lifting a box to place it on a shelf
• D. Holding a book stationary in your hand

Correct answer: c

Rationale: Work is done when a force is applied to move an object over a distance.

4. Which of the following is NOT a characteristic of living organisms?

• A. Made up of cells
• B. Able to reproduce
• C. Require energy
• D. Non-motile

Correct answer: D

Rationale: Rationale: A) Made up of cells: All living organisms are composed of one or more cells. This is a fundamental characteristic of life as defined by cell theory. B) Able to reproduce: One of the key characteristics of living organisms is their ability to reproduce and pass on genetic information to offspring. C) Require energy: Living organisms require energy to carry out various life processes such as growth, reproduction, and maintenance of homeostasis. This energy is obtained through processes like metabolism. D) Non-motile: While some living organisms may be non-motile (unable to move on their own), movement is a common characteristic of many living organisms. Motility allows organisms to respond to their environment, find food, escape predators, and carry out other essential activities.

5. What property of matter remains constant regardless of changes in its state?

• A. Mass
• B. Volume
• C. Density
• D. Weight

Correct answer: a

Rationale: Mass remains constant for a given amount of matter, regardless of its state (solid, liquid, or gas) or its location in the universe. Explanation of other options:

6. What type of force opposes the motion of an object moving through a fluid (liquid or gas)?

• A. Gravitational force
• B. Tension force
• C. Viscous force
• D. Magnetic force

Correct answer: c

Rationale: Viscous force is the resistance experienced by an object moving through a fluid due to internal friction.

Similar Questions