a force of 12 kg stretches a spring 3 cm how far will the spring stretch given a force of 30 kg

HESI A2

HESI A2 Physics

1. If a force of 12 kg stretches a spring by 3 cm, how far will the spring stretch when a force of 30 kg is applied?

A. 6 cm
B. 7.5 cm
C. 9 cm
D. 10.5 cm

Correct answer: B

Rationale: The extension of a spring is directly proportional to the force applied. In this case, the force increases from 12 kg to 30 kg, which is a 2.5 times increase. Therefore, the extension of the spring will also increase by 2.5 times. Given that the spring stretches 3 cm with a force of 12 kg, multiplying 3 cm by 2.5 gives us the extension of the spring when a force of 30 kg is applied, which equals 7.5 cm. Therefore, the correct answer is 7.5 cm. Choice A, 6 cm, is incorrect because it does not account for the proportional increase in force. Choice C, 9 cm, and Choice D, 10.5 cm, are incorrect as they overestimate the extension of the spring by not considering the direct proportionality between force and extension.

2. Which gland controls Calciferol?

A. Thyroid
B. Pituitary
C. Parathyroid
D. Hypothalamus

Correct answer: C

Rationale: Calciferol, commonly known as Vitamin D, is regulated by the parathyroid gland, not the thyroid, pituitary, or hypothalamus. The parathyroid gland plays a crucial role in maintaining calcium and phosphorus balance in the body by regulating the production of calcitriol, the active form of Vitamin D. This hormone helps in the absorption of calcium from the intestines and its reabsorption in the kidneys to maintain proper calcium levels in the blood. Therefore, the correct answer is the Parathyroid gland (Choice C). Choices A, B, and D are incorrect as they do not have a direct role in controlling Calciferol.

3. Select the phrase or clause that is misplaced in the following sentence. With torn pages, I returned the book I’d just bought to the store.

A. With torn pages
B. I returned the book
C. I’d just bought
D. to the store

Correct answer: A

Rationale: The phrase 'With torn pages' is misplaced in the sentence because it disrupts the flow of the sentence. Placing it at the beginning creates an awkward structure. It would be clearer to present the main action first before adding the detail about the torn pages. In this case, rearranging the sentence to 'I returned the book I’d just bought to the store with torn pages' would improve the sentence's coherence and readability. Choices B, C, and D are not misplaced in the sentence as they follow a logical order of action and description.

4. The price of an item increased from $9.00 to $10.00. What percentage did the price increase by?

A. 5%
B. 11.11%
C. 20%
D. 25%

Correct answer: B

Rationale: To calculate the percentage increase, subtract the original price from the new price, then divide the result by the original price and multiply by 100. In this case, the increase is $10.00 - $9.00 = $1.00. $1.00 divided by $9.00 is approximately 0.1111, which equals 11.11%, making choice B the correct answer. Choice A, 5%, is too low as the increase is more than 5%. Choice C, 20%, and choice D, 25%, are too high, exaggerating the actual increase of $1.00.