| 1 |
|
(a) |
|
Each collision with the walls reduces the kinetic energy of the point-like mass by a factor of 1/2, as it loses half of its kinetic energy to thermal energy. using the equation E * (1/2)^n and substituting in 8 to find the collisions needed to reduce by 8. so the equation will look like E * (1/2)^n = E / 8. after solving, we will get n = 3. So, it would take 3 collisions with the walls for the speed of the mass to be reduced by a factor of 8. |
using the equation E * (1/2)^n
https://openstax.org/books/university-physics-volume-1/pages/6-2-friction
https://phys.libretexts.org/Bookshelves/University_Physics/Book%3A_University_Physics_(OpenStax)/Book%3A_University_Physics_I_-_Mechanics_Sound_Oscillations_and_Waves_(OpenStax)/15%3A_Oscillations/15.03%3A_Energy_in_Simple_Harmonic_Motion |
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 2 |
|
(a) |
|
Initially, the mass is at rest, so its initial kinetic energy is zero. The only form of energy is the potential energy stored in the spring. we will use the equation: U = (1/2)kx^2. |
https://en.wikipedia.org/wiki/Stokes%27_law
https://www.sciencedirect.com/topics/engineering/hookean-spring |
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 3 |
|
(c) |
|
|
https://www.khanacademy.org/science/high-school-physics/two-dimensional-motion-2/friction/a/friction-ap-physics-1
https://www.omnicalculator.com/physics/inclined-plane
https://www.school-for-champions.com/science/friction_sliding_static_incline.htm
https://openstax.org/books/physics/pages/5-4-inclined-planes |
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 4 |
|
(d) |
|
The rotational inertia of a solid sphere about an axis through its center can be calculated using the formula: I = (2/5) * m * r^2. So, the rotational inertia of the second sphere is 16 times that of the first sphere, assuming they have the same density and the second sphere has twice the radius. |
https://physics.stackexchange.com/questions/281077/effect-of-density-and-volume-on-inertia
https://socratic.org/questions/how-does-density-affect-the-moment-of-inertia
https://openstax.org/books/university-physics-volume-1/pages/10-5-calculating-moments-of-inertia
https://www.khanacademy.org/science/physics/torque-angular-momentum/torque-tutorial/a/rotational-inertia |
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 5 |
|
(e) |
|
Momentum (p) = Force (F) * Distance (d), p = F * d, he rocket with mass 9m acquires momentum P when the same constant force F acts on it for the same distance d. The momentum acquired by the rocket with mass 9m is proportional to its mass, just like in the first case, but it will be 9 times greater: P = 9 * p. So, the rocket with mass 9m acquires 9 times the momentum compared to the rocket with mass m when the same force is applied for the same distance. |
https://en.wikipedia.org/wiki/Gravitational_field
https://revisionscience.com/a2-level-level-revision/physics-level-revision/fields/gravitational-fields
ttps://www.khanacademy.org/science/hs-physics/x215e29cb31244fa1:types-of-interactions/x215e29cb31244fa1:newton-s-law-of-universal-gravitation/a/newtons-law-of-universal-gravitation
https://phys.libretexts.org/Bookshelves/University_Physics/Book%3A_University_Physics_(OpenStax)/Book%3A_University_Physics_I_-_Mechanics_Sound_Oscillations_and_Waves_(OpenStax)/09%3A_Linear_Momentum_and_Collisions/9.11%3A_Rocket_Propulsion |
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 6 |
|
(E) |
|
E0 = mgh +12mv20 = 2Ef = 2mg(2h). |
https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:kinetic-energy/v/kinetic-energy-ms
|
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 7 |
|
(E) |
|
the point of the ball with the maximum speed is the one at the very bottom of the ball, which is in contact with the surface of the chute. This point is the point of tangency between the ball and the surface and has the highest linear speed because it covers the greatest distance in the same amount of time as the ball rolls down the chute without slipping. |
https://study.com/academy/lesson/point-of-tangency-definition-example.html
https://byjus.com/physics/velocity/ |
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 8 |
|
(B) |
|
If the astronaut throws a piece of trash to their left, it will have a velocity in the direction opposite to the space station's travel. However, because there is no significant air resistance or gravitational force acting on the trash, it will continue to move in a straight line at a constant velocity. It won't return to the space station unless it collides with the station or another object. If the astronaut throws a piece of trash to their right, it will have a velocity in the same direction as the space station's travel. Similarly, because there is no significant air resistance or gravitational force acting on the trash, it will continue to move in a straight line at a constant velocity, in the direction of the space station's travel. It also won't return to the space station unless it collides with the station or another object. If the astronaut throws a piece of trash upward, it will initially move in the direction of the throw. However, the trash will continue to be in orbit around the Earth due to the space station's orbital velocity and its distance from the Earth's surface. In this case, the trash will continue to orbit the Earth and eventually return to the space station after several hours. This behavior is due to the gravitational attraction between the trash and the Earth, which keeps it in orbit. only the piece of trash thrown upward (III) will return to the space station due to its orbital path, while the other two pieces (I and II) will continue in their respective directions unless they encounter obstacles or other forces. |
https://www.khanacademy.org/computing/computer-programming/programming-natural-simulations/programming-forces/a/gravitational-attraction
https://www.britannica.com/science/Newtons-law-of-gravitation
https://space-facts.com/planet-orbits/
https://byjus.com/physics/velocity/
https://education.nationalgeographic.org/resource/orbit/ |
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 9 |
|
(d) |
|
|
https://www.khanacademy.org/science/physics/linear-momentum/elastic-and-inelastic-collisions/a/what-are-elastic-and-inelastic-collisions
http://hyperphysics.phy-astr.gsu.edu/hbase/elacol.html |
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 10 |
|
(a) |
|
The time at which the tangential component of acceleration is twice the perpendicular component of acceleration is when the object reaches the ground. The time is independent of the initial speed, and in this case, it's when the object falls to the ground from the 50.0-meter height. |
https://phys.libretexts.org/Bookshelves/University_Physics/Book%3A_Physics_(Boundless)/3%3A_Two-Dimensional_Kinematics/3.3%3A_Projectile_Motion
https://physics.stackexchange.com/questions/129701/how-to-approximate-acceleration-from-a-trajectorys-coordinates
https://openstax.org/books/physics/pages/3-1-acceleration |
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 11 |
|
A. false
B. true
C. true
D. false |
|
A. A low H² value of a trait doesn't necessarily indicate that the trait is determined mainly by the environment. It means that a lower proportion of the phenotypic variance is due to genetic factors, but it doesn't specify the importance of the environment.
B. Genetic variance can depend on the environment to which the population is exposed. Environmental factors can affect gene expression, gene interactions, and other genetic processes.
C. Artificial selection for a trait with higher h² is generally more successful because a larger proportion of the phenotypic variance is attributable to genetic factors. This means that offspring are more likely to inherit the desired trait, leading to more rapid and predictable changes in the trait in successive generations.
D. not enough information given to determine |
https://www.encyclopedia.com/science-and-technology/biology-and-genetics/genetics-and-genetic-engineering/genetic-variance
https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/genetic-variance
https://www.ncbi.nlm.nih.gov/books/NBK425811/
https://www.britannica.com/science/evolution-scientific-theory/Genetic-variation-and-rate-of-evolution |
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 12 |
|
Heritability measures the proportion of the total phenotypic variance that can be attributed to additive genetic variance. |
|
Enfield determined that h² for the selected population after 125 generations was only slightly less than for the original population. This means that, despite the significant increase in body size, there was still a strong genetic basis for body size in the selected population. This means that the selected population retained a strong genetic basis for body size, even though selection had significantly increased the mean weight. This indicates that there was still genetic diversity in the selected population for body size, allowing for continued selection and improvement. However, it's important to note that, after 125 generations, further selection did not result in a further increase in size, suggesting that the population might have reached a limit or that other factors began to constrain further growth. |
https://academic.oup.com/evolut/article/50/2/723/6870602
https://www.frontiersin.org/articles/10.3389/fncel.2023.1097462/full
https://www.nature.com/articles/srep34813 |
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 13 |
|
When the mutated male mates with the normal female, there is a significantly higher percentage of degeneration after implantation compared to when a normal male mates with a normal female. |
|
The data indicates that when the mutated male mates with the normal female, there is a significantly higher percentage of degeneration after implantation compared to when a normal male mates with a normal female. the mutation in the male mouse may be affecting the viability and development of embryos after implantation, resulting in a higher rate of degeneration. The specific genetic or physiological factors underlying this anomaly would require further investigation to understand the cause. |
https://en.wikipedia.org/wiki/Endometrium |
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 14 |
|
A. true
B. true
C. false
D. true |
|
A. This is because species can diversify and adapt to different ecological niches, leading to increased speciation within a lineage.
B. Animal pollination can result in more precise and efficient pollen transfer, increasing the likelihood of successful reproduction and speciation.
C. Complex mating behaviors, such as elaborate courtship rituals, can contribute to reproductive isolation, which is a key driver of speciation. In some cases, these behaviors can lead to the formation of new species
D. Changes in climate can alter habitats and ecological conditions, which can drive the evolution of new species as they adapt to different environments. Climate fluctuations may lead to periods of increased speciation when new ecological opportunities arise. |
https://www.sciencedirect.com/topics/earth-and-planetary-sciences/climate-oscillation
https://storymaps.arcgis.com/stories/d62f89509b504633a2c7516ab12d7767 |
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 15 |
|
A. false
B. true
C. false
D. true |
|
A. In this population, the number of persons with blood groups A and B will not necessarily be equal. The ABO blood group system is controlled by multiple alleles, including A and B, and the phenotypes depend on the specific combinations of these alleles. The frequencies of these alleles (p(A) and p(B)) being equal does not guarantee an equal number of individuals with blood groups A and B.
B. Blood group AB individuals have both A and B alleles, and if the frequencies of these alleles are equal (p(A) = p(B)), then there should be an equal number of individuals with blood groups A and AB.
C. The frequency of persons with anti-B antibodies cannot be determined from the allele frequencies alone. The presence of anti-B antibodies in an individual depends on their specific ABO blood group genotype. It's not directly related to the frequencies of ABO alleles in the population.
D. The equal frequencies indicate that it is autosomal and inherited similarly in both men and women. |
http://www.biology.arizona.edu/human_bio/ABO_Crosses.html
https://www.ncbi.nlm.nih.gov/books/NBK2267/
https://www.britannica.com/science/blood-group/Blood-groups-and-genetic-linkage |
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 16 |
|
A. true
B. false
C. true
D. true |
|
A. The fitness of these alleles decreases as they become more common in the population because when they are rare, they are more likely to find compatible mating partners. As their frequency increases, the likelihood of encountering a compatible partner decreases, reducing their fitness.
B. Viruses often spread based on their ability to infect and transmit from one host to another, and their fitness doesn't necessarily decrease as they become more common in the population.
C. In this case, the fitness of the mimicry phenotype increases as it becomes more common because predators learn to avoid it based on the abundance of distasteful prey. The more common the mimicry phenotype, the more protected it is.
D. The fitness of the warning coloration phenotype increases as it becomes more common. Predators learn to associate the coloration with unpalatability or toxicity, and as it becomes more prevalent, it provides greater protection to individuals with the warning coloration. |
https://www.nature.com/articles/s41576-020-0234-z |
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 17 |
|
The UV imaging of the plants likely allowed researchers to visually confirm whether GFP expression was effectively silenced by the treatment RNAs and whether this silencing was maintained in the next generation. |
|
The experiment is designed to investigate how RNA-directed gene silencing affects the expression of the GFP gene in plants and whether this silencing effect is passed on to the next generation. By using complementary RNAs specific to different regions of the GFP gene, the researchers can study how gene silencing mechanisms operate. This type of research is important for understanding the regulation of gene expression and developing methods for gene silencing in plants, which can have various applications in biotechnology and agriculture. |
|
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 18 |
|
The aim of these experiments is to gain insights into how the Slit-Robo signaling pathway, regulated by the Comm transcription factor, influences the growth and guidance of neurons in Drosophila embryos. |
|
The aim of these experiments is to gain insights into how the Slit-Robo signaling pathway, regulated by the Comm transcription factor, influences the growth and guidance of neurons in Drosophila embryos. By comparing the behaviors of these different groups of flies, researchers can draw conclusions about the roles of these proteins and factors in neuron development and guidance. |
https://www.britannica.com/technology/biotechnology |
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 19 |
|
This mapping of protein locations and interactions is crucial for gaining insights into cellular processes, signaling pathways, and the regulation of various biological functions. |
|
Mapping protein locations in cells is a foundational aspect of cell biology that has far-reaching implications for understanding biology, medicine, and biotechnology, ultimately leading to improved health and our understanding of life's fundamental processes. |
|
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|
| 20 |
|
Jean Hanson's work on muscle contraction and the role of calcium is indeed significant in the field of biology. |
|
This information outlines the fundamental processes by which calcium ions play a central role in muscle contraction and relaxation. It demonstrates how the regulation of calcium movement and concentration within muscle cells is crucial for the proper functioning of muscle tissue. Jean Hanson's research contributions have significantly advanced our understanding of these processes. The knowledge about calcium regulation in muscle cells has broad applications in research, healthcare, and technology, contributing to advancements in various fields and improving our understanding of human physiology and health. |
https://www.kcl.ac.uk/people/jean-hanson
https://pubmed.ncbi.nlm.nih.gov/25296301/ |
7 |
-.50
-.25
+.25
เต็ม
0
-35%
+30%
+35%
|