how does kinetic energy change when the velocity of an object is doubled

ATI TEAS 7

TEAS Test 7 science quizlet

1. How does kinetic energy change when the velocity of an object is doubled?

A. Kinetic energy is halved
B. Kinetic energy quadruples
C. Kinetic energy doubles
D. Kinetic energy remains the same

Correct answer: B

Rationale: Kinetic energy is directly proportional to the square of the velocity of an object according to the kinetic energy formula (KE = 0.5 * m * v^2). When the velocity is doubled, the kinetic energy increases by a factor of 2^2 = 4. Therefore, the kinetic energy quadruples when the velocity of an object is doubled. Choice A is incorrect because halving the kinetic energy would be the result if the velocity was halved, not doubled. Choice C is incorrect because doubling the velocity would result in a fourfold increase in kinetic energy, not just a double. Choice D is incorrect because kinetic energy is directly related to the velocity of an object, so if the velocity changes, the kinetic energy changes accordingly.

2. Which cellular organelle is used for digestion to recycle materials?

A. The Golgi apparatus
B. The lysosome
C. The centrioles
D. The mitochondria

Correct answer: B

Rationale: The lysosome is the correct cellular organelle used for digestion to recycle materials. Lysosomes contain enzymes that break down waste materials, cellular debris, and ingested substances. This process helps in recycling nutrients and maintaining cellular homeostasis. The Golgi apparatus is involved in processing and packaging proteins, the centrioles play a role in cell division, and the mitochondria are responsible for energy production. However, none of these organelles are primarily used for digestion and recycling of materials within the cell.

3. Which of the following structures in the skin is responsible for producing sweat?

A. Sebaceous gland
B. Sudoriferous gland
C. Hair follicle
D. Melanocyte

Correct answer: B

Rationale: The correct answer is B: Sudoriferous gland. Sudoriferous glands, also known as sweat glands, are responsible for producing sweat to regulate body temperature. Sebaceous glands produce sebum (oil) to lubricate the skin and hair. Hair follicles are associated with hair growth, not sweat production. Melanocytes are responsible for producing melanin for skin pigmentation, not sweat.

4. A ball is rolling across the floor and comes to a stop on its own. What force caused the ball to stop?

A. Gravitational force
B. Normal force from the floor
C. Air resistance
D. None of the above

Correct answer: C

Rationale: The force that caused the ball to stop rolling across the floor is air resistance. As the ball moves through the air, air resistance acts in the opposite direction of its motion, gradually slowing it down until it comes to a stop. In this scenario, the ball is not in contact with the floor, so the normal force from the floor does not play a role in stopping the ball. Gravitational force acts to pull objects towards the center of the Earth and would not directly stop the ball in this situation. Therefore, air resistance is the force that opposes the motion of the rolling ball and causes it to come to a stop.

5. The Minimum Inhibitory Concentration (MIC) of an antibiotic refers to:

A. The lowest concentration that kills bacteria
B. The dose required for 50% bacterial inhibition
C. The time it takes for an antibiotic to work
D. The spectrum of bacteria the antibiotic targets

Correct answer: B

Rationale: A) The lowest concentration that kills bacteria is known as the Minimum Bactericidal Concentration (MBC), not the Minimum Inhibitory Concentration (MIC). MIC is the lowest concentration of an antibiotic that inhibits visible growth of bacteria. B) The MIC of an antibiotic is the concentration at which bacterial growth is inhibited by 50%. This concentration is used to determine the effectiveness of an antibiotic against a specific bacterium. C) The time it takes for an antibiotic to work is not described by the MIC. MIC is a measure of concentration, not time. D) The spectrum of bacteria the antibiotic targets is not defined by the MIC. The MIC value is specific to a particular antibiotic and bacterium, regardless of the spectrum of activity of the antibiotic.