Nursing Elites

1. In Einstein’s mass-energy equation, what is represented by c?

• A. Distance in centimeters
• B. The speed of light
• C. Degrees Celsius
• D. Centrifugal force

Correct answer: B

Rationale: In Einstein's mass-energy equation, E=mc^2, the symbol 'c' represents the speed of light in a vacuum, which is approximately equal to 3.00 x 10^8 meters per second. This equation demonstrates the equivalence of energy (E) and mass (m) and is a fundamental concept in the theory of relativity. Choice A is incorrect as 'c' does not represent distance in centimeters. Choice C is incorrect as 'c' does not represent degrees Celsius. Choice D is incorrect as 'c' does not represent centrifugal force.

2. Given the four wires described here, which would you expect to have the greatest resistance?

• A. 1 km of American wire gauge 1; diameter 7.35 mm
• B. 1 km of American wire gauge 2; diameter 6.54 mm
• C. 1 km of American wire gauge 3; diameter 5.83 mm
• D. 1 km of American wire gauge 4; diameter 5.19 mm

Correct answer: D

Rationale: The wire with the greatest resistance is the one with the smallest diameter, as resistance is inversely proportional to cross-sectional area. Gauge 4 with a 5.19 mm diameter has the smallest diameter and, therefore, the greatest resistance. Choice A, B, and C have larger diameters compared to choice D, so they would have lower resistance values.

3. A key parameter in fluid selection is specific gravity (SG). For a submerged object in a reference fluid (often water), SG = ρ_object / ρ_reference. An object with SG > 1 will:

• A. Experience a net buoyant force acting upwards
• B. Experience a net buoyant force acting downwards
• C. Remain neutrally buoyant
• D. Require knowledge of the object's volume for buoyancy determination

Correct answer: A

Rationale: When the specific gravity (SG) of an object is greater than 1, it indicates that the object is denser than the reference fluid, which is often water. According to Archimedes' principle, an object with SG > 1 will experience a net buoyant force acting upwards when submerged in the fluid. This is because the buoyant force is greater than the weight of the object, causing it to float. Therefore, the correct answer is A: 'Experience a net buoyant force acting upwards.' Objects with SG < 1 would sink as they are less dense than the fluid, while objects with SG = 1 would be neutrally buoyant, neither sinking nor floating.

4. Jack stands in front of a plane mirror. If he is 5 feet away from the mirror, how far away from Jack is his image?

• A. 2.5 feet
• B. 3 feet
• C. 4.5 feet
• D. 5 feet

Correct answer: D

Rationale: When Jack stands in front of a plane mirror, his image appears the same distance behind the mirror as Jack is in front of it. Therefore, if Jack is 5 feet away from the mirror, his image will also appear 5 feet behind the mirror. The total distance from Jack to his image is the sum of these distances, which equals 10 feet. Choices A, B, and C are incorrect because the image distance is not half of the total distance but the same as the object's distance from the mirror.

5. In a U-tube manometer, a fluid is used to measure pressure differences. When one side is connected to a pressurized system, the fluid level on that side will:

• A. Remain the same
• B. Decrease
• C. Increase
• D. Depend on the type of fluid used

Correct answer: B

Rationale: In a U-tube manometer, the side connected to a pressurized system will experience a decrease in fluid level due to the pressure exerted by the system. This pressure forces the fluid down, causing the fluid level to decrease. Therefore, choice B is correct. Choices A and C are incorrect because the fluid level will not remain the same or increase when connected to a pressurized system. Choice D is incorrect as the type of fluid used does not determine the direction of the fluid movement in response to pressure.

Similar Questions