Nursing Elites

1. A car, starting from rest, accelerates at 10 m/s² for 5 seconds. What is the velocity of the car after 5 seconds?

• A. 2 m/s
• B. 5 m/s
• C. 50 m/s
• D. The answer cannot be determined from the information given.

Correct answer: C

Rationale: The velocity of an object can be calculated using the formula: final velocity = initial velocity + (acceleration × time). In this case, the car starts from rest, so the initial velocity is 0 m/s. Given that the acceleration is 10 m/s² and the time is 5 seconds, we can plug these values into the formula to find the final velocity: final velocity = 0 m/s + (10 m/s² × 5 s) = 0 m/s + 50 m/s = 50 m/s. Therefore, the velocity of the car after 5 seconds is 50 m/s. Choice A (2 m/s) and Choice B (5 m/s) are incorrect because they do not consider the acceleration the car undergoes over the 5 seconds, resulting in a final velocity greater than both. Choice D (The answer cannot be determined from the information given) is incorrect as the final velocity can be determined using the provided data and the kinematic equation.

2. According to the Law of Universal Gravitation, the gravitational force between two objects is directly proportional to what factor?

• A. the gravitational constant
• B. the distance between them
• C. the product of their masses
• D. the square of the distance between them

Correct answer: C

Rationale: According to the Law of Universal Gravitation, the gravitational force between two objects is directly proportional to the product of their masses. The equation is: F = G × (m₁ × m₂) / r², where F is the gravitational force, G is the gravitational constant, m₁ and m₂ are the masses of the two objects, and r is the distance between them. Choice A is incorrect because the gravitational constant is a constant value. Choice B is incorrect because the distance between the objects affects the strength of the gravitational force inversely proportional to the square of the distance, not directly proportional. Choice D is incorrect as it represents the inverse square law, where the gravitational force decreases with the square of the distance between the objects.

3. When a junked car is compacted, which statement is true?

• A. Its mass increases.
• B. Its mass decreases.
• C. Its density increases.
• D. Its density decreases.

Correct answer: C

Rationale: When a junked car is compacted, its volume decreases while its mass remains the same. As a result, the car's density increases because density is mass divided by volume. Choice A is incorrect because the mass of the car remains the same. Choice B is incorrect because the mass does not decrease. Choice D is incorrect because the density increases as the volume decreases, not decreases.

4. 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.

5. When a dielectric material is inserted between the plates of a charged capacitor, what will happen to the capacitance?

• A. Increase
• B. Decrease
• C. Remain the same
• D. Become unpredictable

Correct answer: A

Rationale: When a dielectric material is inserted between the plates of a charged capacitor, the capacitance will increase. This is because the presence of a dielectric material reduces the electric field between the plates, allowing more charge to be stored for a given voltage, thus increasing the capacitance. Choice B is incorrect because adding a dielectric material increases capacitance. Choice C is incorrect because capacitance changes when a dielectric is added. Choice D is incorrect because the effect of a dielectric on capacitance is predictable.

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