General Fundamental Scientific Principles Questions and Answers — Questions and Answers
Question 1: A pendulum swings back and forth in a closed system with negligible air resistance. At the highest point of its swing, which statement is true regarding its energy?
- Kinetic energy is at a maximum; potential energy is at a minimum.
- Both kinetic and potential energy are at their maximum.
- Kinetic energy is at a minimum; potential energy is at a maximum. (Correct answer)
- Both kinetic and potential energy are zero.
Correct answer: Kinetic energy is at a minimum; potential energy is at a maximum.
At the peak of its swing, the pendulum bob momentarily stops before changing direction. Since kinetic energy is the energy of motion (1/2 * mass * velocity^2), it is at a minimum (zero) when the velocity is zero. Potential energy is stored energy due to position (mass * gravity * height). At the highest point, the potential energy is at its maximum.
Question 2: Which of the following correctly describes the central dogma of molecular biology, representing the primary flow of genetic information in most organisms?
- Protein → RNA → DNA
- DNA → RNA → Protein (Correct answer)
- RNA → DNA → Protein
- DNA → Protein → RNA
Correct answer: DNA → RNA → Protein
The central dogma states that genetic information flows from DNA to RNA through a process called transcription, and then from RNA to protein through a process called translation. This sequence describes how the genetic code is used to build functional products.
Question 3: A scientist wants to test the effect of different light colors on the growth rate of a specific type of bean plant. They place identical plants in separate chambers, with each chamber having a different colored light (red, blue, green), but all other conditions (water, soil, temperature) are kept the same. In this experiment, what is the independent variable?
- The growth rate of the bean plants.
- The type of bean plant used.
- The amount of water given to the plants.
- The color of the light. (Correct answer)
Correct answer: The color of the light.
The independent variable is the factor that the experimenter intentionally changes or manipulates to observe its effect. In this case, the scientist is changing the color of the light to see how it impacts growth. The growth rate is the dependent variable (what is measured), while the plant type, water, and temperature are controlled variables.
Question 4: Which of the following is an example of a chemical change, where a new substance is formed?
- An iron nail rusting (Correct answer)
- Water boiling into steam
- Sugar dissolving in tea
- An ice cube melting
Correct answer: An iron nail rusting
The rusting of an iron nail is a chemical change because a new substance, iron oxide (rust), is formed through an oxidation reaction between iron and oxygen. The other options are physical changes, where the substance's form or state changes but its chemical identity (H₂O or C₁₂H₂₂O₁₁) remains the same.
Question 5: According to the theory of plate tectonics, what is considered the primary driving force behind the movement of Earth's lithospheric plates?
- The gravitational pull of the Sun and Moon.
- Convection currents within the Earth's mantle. (Correct answer)
- Erosion and weathering on the Earth's surface.
- The rotation of the Earth on its axis (Coriolis effect).
Correct answer: Convection currents within the Earth's mantle.
The most widely accepted theory is that the movement of tectonic plates is driven by convection currents in the mantle. Hot, less-dense material from deep within the mantle rises, cools, and then sinks, creating a circular motion that drags the overlying tectonic plates along.
Question 6: A rocket propels itself upward by expelling hot gases downward. This phenomenon is a direct application of which of Newton's Laws of Motion?
- Newton's First Law (Inertia)
- Newton's Law of Universal Gravitation
- Newton's Third Law (Action-Reaction) (Correct answer)
- Newton's Second Law (F=ma)
Correct answer: Newton's Third Law (Action-Reaction)
This is a classic example of Newton's Third Law of Motion, which states that for every action, there is an equal and opposite reaction. The rocket pushing the gas down (action) results in the gas pushing the rocket up (reaction) with an equal and opposite force.
General Fundamental Scientific Principles Questions and Answers
A pendulum swings back and forth in a closed system with negligible air resistance.
At the highest point of its swing, which statement is true regarding its energy?