Which statement accurately defines power?
- A. Power is the amount of energy stored in an object
- B. Power is the rate at which energy is transferred or work is done
- C. Power is the maximum force exerted by an object
- D. Power is the resistance of an object to change in motion
Correct Answer: B
Rationale: Power is defined as the rate at which energy is transferred or work is done. It is a measure of how quickly work is done or energy is transferred. Option A incorrectly refers to the amount of energy stored in an object, not power. Option C incorrectly refers to the maximum force exerted by an object, not power. Option D incorrectly refers to the resistance of an object to change in motion, not power. Therefore, the correct definition of power is that it is the rate at which energy is transferred or work is done.
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How does an increase in mass affect the force required to produce the same acceleration on an object?
- A. Increases force required
- B. Decreases force required
- C. Has no effect on force required
- D. Causes unpredictable changes in force required
Correct Answer: A
Rationale: The correct answer is A, 'Increases force required.' According to Newton's second law of motion, force is directly proportional to mass and acceleration (F = ma). Therefore, an increase in mass will require an increase in force to produce the same acceleration on an object. Choice B is incorrect because an increase in mass does not decrease the force required; it increases it. Choice C is incorrect as increasing mass does affect the force required. Choice D is incorrect as the relationship between mass and force is predictable according to Newton's laws of motion.
Which of the following best describes a balanced force acting on an object?
- A. The object remains at rest
- B. The object moves with constant velocity
- C. The object accelerates
- D. The object's mass changes
Correct Answer: B
Rationale: When a balanced force acts on an object, the net force is zero, resulting in no acceleration. This means that the object will continue to move with a constant velocity if it was already in motion or remain at rest if it was initially stationary. Choice A is incorrect because the object can also move with constant velocity. Choice C is incorrect as acceleration only occurs when an unbalanced force is applied. Choice D is incorrect as the mass of an object is not affected by the balance of forces acting on it.
Which division of the autonomic nervous system is responsible for the 'rest and digest' response, promoting relaxation and conservation of energy?
- A. Sympathetic nervous system
- B. Parasympathetic nervous system
- C. Somatic nervous system
- D. Central nervous system
Correct Answer: B
Rationale: The correct answer is B: Parasympathetic nervous system. The parasympathetic nervous system is responsible for the 'rest and digest' response, promoting relaxation, conserving energy, and facilitating activities like digestion and lowering heart rate. The sympathetic nervous system, which is not the correct answer, triggers the 'fight or flight' response, preparing the body for stressful situations by increasing heart rate, dilating airways, and releasing adrenaline. The somatic nervous system (choice C) controls voluntary movements, not the autonomic functions related to 'rest and digest.' The central nervous system (choice D) includes the brain and spinal cord and is not specifically involved in the autonomic regulation of bodily functions like the 'rest and digest' response.
What is the primary function of the large intestine?
- A. Digesting and absorbing nutrients
- B. Storing and mixing food
- C. Breaking down carbohydrates
- D. Absorbing water and electrolytes
Correct Answer: D
Rationale: The primary function of the large intestine is to absorb water and electrolytes from the indigestible food matter that passes through it. This absorption process aids in the formation of solid waste (feces) before it is excreted from the body. Choices A, B, and C are incorrect because the large intestine does not primarily digest and absorb nutrients, store and mix food, or break down carbohydrates. These functions are primarily carried out by the small intestine.
After water absorption in the large intestine, what waste product remains and is eventually eliminated from the body?
- A. Chyme
- B. Bolus
- C. Glucose
- D. Feces
Correct Answer: D
Rationale: The correct answer is D: Feces. After the large intestine absorbs water and electrolytes from digested food material, the waste product that remains is feces. Feces consist of undigested food material, bacteria, and waste products that were not absorbed by the body. Choice A, Chyme, is incorrect as chyme is a semi-fluid mass of partially digested food that moves from the stomach to the small intestine. Choice B, Bolus, is incorrect as bolus refers to a rounded mass of food that is swallowed. Choice C, Glucose, is incorrect as glucose is a simple sugar that serves as a vital energy source for the body and is not a waste product in this context.
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