Nursing Elites

1. When a car brakes to a stop, friction between the tires and the road acts as:

• A. A balanced force
• B. An unbalanced force causing deceleration
• C. An unbalanced force causing the car to remain at rest
• D. No force at all

Correct answer: B

Rationale: When a car brakes to a stop, friction between the tires and the road acts as an unbalanced force causing deceleration. This friction force opposes the motion of the car, resulting in a decrease in speed until the car comes to a complete stop. Choice A is incorrect because if the forces were balanced, the car would not experience any deceleration. Choice C is incorrect because if the force were unbalanced in the direction of motion, the car would continue to move instead of coming to a stop. Choice D is incorrect because friction between the tires and the road does exert a force, causing deceleration.

2. What is the functional group present in aldehydes?

• A. Hydroxyl
• B. Carbonyl
• C. Ester
• D. Amine

Correct answer: B

Rationale: The correct answer is B: Carbonyl. Aldehydes contain the functional group -CHO, which is a carbonyl group where a carbon atom is double-bonded to an oxygen atom and single-bonded to a hydrogen atom. This distinguishes aldehydes from other functional groups. Choice A, Hydroxyl (-OH), is not characteristic of aldehydes as it is found in alcohols. Choice C, Ester (-COOR), and choice D, Amine (-NH2), represent different functional groups not typically found in aldehydes. Therefore, the correct functional group present in aldehydes is the carbonyl group.

3. A ball is thrown horizontally off a cliff. Which of the following forces is responsible for its downward motion?

• A. The force of throwing
• B. Normal force from the air
• C. Tension force from the string (if used)
• D. Gravitational force

Correct answer: D

Rationale: The gravitational force is responsible for the downward motion of the ball. When the ball is thrown horizontally off a cliff, the only force acting on it in the vertical direction is the force of gravity, which pulls the ball downward towards the ground. The other forces mentioned (force of throwing, normal force from the air, tension force from the string) do not contribute to the ball's downward motion in this scenario. The force of throwing initiates the horizontal motion, the normal force from the air opposes the ball's motion through air resistance, and tension force from the string would only be relevant if a string were attached to the ball. Therefore, gravitational force is the primary force responsible for the ball's downward motion in this situation.

4. As a car accelerates from rest, what happens to its kinetic energy and the work done on it?

• A. Both kinetic energy and work done increase.
• B. Kinetic energy increases, but work done remains constant.
• C. Work done increases, but kinetic energy remains constant.
• D. Both kinetic energy and work done remain constant.

Correct answer: A

Rationale: When a car accelerates from rest, its speed and kinetic energy increase. The work done on the car is what increases its kinetic energy, so both kinetic energy and work done increase simultaneously. Option A is correct because acceleration results in an increase in both kinetic energy and the work done on the car. Option B is incorrect because work done is required to increase kinetic energy during acceleration. Option C is incorrect as work done is directly related to the change in kinetic energy. Option D is incorrect as both kinetic energy and work done increase when the car accelerates.

5. What is the function of the stratified cuboidal epithelium lining the salivary glands?

• A. Protection
• B. Gas exchange
• C. Secretion
• D. Absorption

Correct answer: C

Rationale: The correct answer is C: Secretion. The stratified cuboidal epithelium lining the salivary glands is responsible for secretion. This type of epithelium, made of multiple layers of cube-shaped cells, is specialized for secretion and protection. In the salivary glands, these cells secrete saliva to aid in the digestion process. Choice A, Protection, is incorrect because while the epithelium does provide some level of protection, its primary function in the salivary glands is secretion. Choice B, Gas exchange, is incorrect as the salivary glands are not involved in gas exchange processes. Choice D, Absorption, is also incorrect as the main role of this epithelium in the salivary glands is not absorption but rather secretion of saliva.

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