Nokea
When two objects with different masses collide, what happens to their momentum after the collision?
- A. Increases for both objects
- B. Decreases for both objects
- C. Remains the same for both objects
- D. Can increase for one and decrease for the other
Correct Answer: C
Rationale: When two objects with different masses collide, their total momentum remains the same after the collision according to the law of conservation of momentum if no external forces are acting on them. This means that the momentum of each individual object may change, but the sum of their momenta will remain constant. Choice A is incorrect because the total momentum of the system is conserved. Choice B is incorrect because momentum is conserved in an isolated system. Choice D is incorrect as it implies a violation of the law of conservation of momentum, which states that the total momentum of an isolated system remains constant.
You may also like to solve these questions
Which type of joint allows for the widest range of motion, similar to the shoulder joint?
- A. Hinge joint
- B. Ball-and-socket joint
- C. Gliding joint
- D. Fixed joint
Correct Answer: B
Rationale: The correct answer is B: Ball-and-socket joint. Ball-and-socket joints, like the shoulder joint, allow for the widest range of motion in multiple directions. This type of joint consists of a rounded bone (the 'ball') fitting into a cup-like socket, enabling movements such as flexion, extension, abduction, adduction, and rotation. Choice A, Hinge joint, allows movement in one plane, like a door hinge, and does not offer the same range of motion as a ball-and-socket joint. Choice C, Gliding joint, permits limited motion in various directions but not as wide as a ball-and-socket joint. Choice D, Fixed joint, does not allow any motion as it is immovable, unlike the shoulder joint which is highly mobile.
What is the process by which muscle tissue wastes away due to disuse or lack of nutrients?
- A. Hypertrophy
- B. Atrophy
- C. Fibrosis
- D. Rigor mortis
Correct Answer: B
Rationale: Atrophy is the correct term for the process by which muscle tissue wastes away due to disuse or lack of nutrients. It is essential to differentiate atrophy from hypertrophy, which is the increase in muscle size due to exercise or strength training. Fibrosis involves the formation of excess fibrous connective tissue, which is distinct from muscle wasting. Rigor mortis, on the other hand, is the stiffening of muscles that occurs after death and is not related to muscle wasting during life.
What is the medical term for heartburn, a burning sensation in the chest caused by stomach acid?
- A. Dysphagia
- B. Gastroesophageal reflux disease (GERD)
- C. Peptic ulcer
- D. Ulcerative colitis
Correct Answer: B
Rationale: A) Dysphagia refers to difficulty swallowing and is not specifically related to heartburn. B) Gastroesophageal reflux disease (GERD) is the medical term for heartburn, which is a burning sensation in the chest caused by stomach acid flowing back up into the esophagus. C) Peptic ulcer is a sore that develops on the lining of the stomach, small intestine, or esophagus, and it can cause symptoms such as abdominal pain, not specifically heartburn. D) Ulcerative colitis is a type of inflammatory bowel disease that affects the colon and rectum, and it does not typically cause heartburn.
Which of the following describes a scalar quantity?
- A. Velocity
- B. Acceleration
- C. Force
- D. Speed
Correct Answer: D
Rationale: A scalar quantity is a physical quantity that has magnitude only, without any direction. Speed is an example of a scalar quantity because it only describes how fast an object is moving without specifying the direction of motion. Velocity, acceleration, and force are vector quantities because they have both magnitude and direction. Therefore, the correct answer is 'Speed.' Choices A, B, and C are incorrect because velocity, acceleration, and force are all vector quantities that involve both magnitude and direction.
How does the structure of centromeres contribute to chromosome movement during mitosis?
- A. The centromere provides a binding site for spindle fibers, allowing chromosomes to be attached and manipulated.
- B. The centromere serves as a dividing point between sister chromatids, ensuring their separation during anaphase.
- C. The centromere maintains chromosome stability by preventing chromosomal breaks and rearrangements.
- D. The centromere plays a role in DNA replication, ensuring accurate copying of the genetic material.
Correct Answer: A
Rationale: A) The centromere provides a binding site for spindle fibers, which are microtubules that help move chromosomes during cell division. This attachment allows the chromosomes to be pulled towards opposite poles of the cell during mitosis. Therefore, the structure of centromeres directly contributes to chromosome movement during mitosis by facilitating the attachment and manipulation of chromosomes by the spindle fibers.
B) While the centromere does serve as a dividing point between sister chromatids, ensuring their separation during anaphase, this function is more related to the segregation of chromosomes rather than their movement.
C) The centromere does play a role in maintaining chromosome stability by ensuring proper chromosome segregation, but it is not primarily responsible for preventing chromosomal breaks and rearrangements.
D) The centromere is not directly involved in DNA replication. Its main function is