HESI Exams Quizlet Physics

Correct Answer: B

Rationale: The correct answer is B (15.625 cm). To calculate the image height using mirror formula (1/f = 1/v + 1/u), first find the object distance (u) which is -20 cm (since object is placed on the same side as focal point, it is negative). Then, solve for image distance (v) by substituting u and f values. Next, use magnification formula (m = -v/u) to find the magnification factor. Finally, multiply the object height by the magnification factor to get the image height, which is 15.625 cm. Choice A (30.5 cm) is incorrect as it is double the correct answer. Choice C (-15 cm) and choice D (-30.5 cm) are incorrect as the negative sign indicates an inverted image, but in this case, the image is upright.

Correct Answer: A

Rationale: The momentum of an object is calculated by multiplying its mass by its velocity. In this case, for option A, the momentum of the car is calculated as 1,250 kg x 5 m/s = 6,250 kg*m/s. This is greater than the momentum of the other choices. For option B, the momentum of the person is 80 kg x 4 m/s = 320 kg*m/s, which is less than the car's momentum. For option C, the momentum of the meteorite is 10 kg x 600 m/s = 6,000 kg*m/s, which is also less than the car's momentum. For option D, the momentum of the rock is 0.5 kg x 40 m/s = 20 kg*m/s, making it the smallest momentum among the choices. Therefore, the car moving at 5 m/s has the greatest momentum due to its higher mass and velocity compared to the other objects.

Correct Answer: A

Rationale: The correct answer is A: Q = cΔT. This equation represents the definition of specific heat capacity, where Q (heat transfer) is equal to the product of c (specific heat capacity) and ΔT (temperature change) for a unit mass of the material. This equation is derived from the formula for heat transfer, Q = mcΔT, by dividing both sides by mass 'm'. Therefore, the correct equation is Q = cΔT. Summary of other choices: B: Q = mcΔT - This is the formula for total heat transfer, not specific heat capacity. C: Q = c / mΔT - This equation does not accurately represent the relationship between specific heat capacity, heat transfer, temperature change, and mass. D: Q = ΔT / mc - This equation is not a correct representation of specific heat capacity and does not follow the standard formula.

Correct Answer: B

Rationale: The correct answer is B: Decrease. When one side of the U-tube manometer is connected to a pressurized system, the pressure on that side will be higher, causing the fluid level to decrease due to the increase in pressure. This is because the pressure difference between the two sides of the manometer causes the fluid to move towards the side with higher pressure. Choice A is incorrect because the fluid level will not remain the same in response to the pressure change. Choice C is incorrect as the fluid level will decrease, not increase. Choice D is incorrect as the type of fluid used does not affect how the fluid level changes in response to pressure.

Correct Answer: B

Rationale: To determine the power rating of the lamp, we use the formula Power = Energy / Time. Given the lamp consumes 60 Joules per second, the power rating is 60 Joules / 1 second = 60 Watts (Choice B). The other choices are incorrect because A is too low, C is not a valid unit for power, and D is not necessary as power can be calculated based on energy consumption alone.