OTEE - Officer Trainee Entrance General Science Principles Questions and Answers 1 — Questions and Answers
Question 1: An individual is standing on a scale in an elevator that is accelerating upwards. How will the reading on the scale compare to their actual weight?
- The reading will be lower than the actual weight.
- The reading will be higher than the actual weight. (Correct answer)
- The reading will be the same as the actual weight.
- The reading will be zero.
Correct answer: The reading will be higher than the actual weight.
According to Newton's Second Law (F=ma), when the elevator accelerates upward, the normal force exerted by the scale on the person must be greater than the force of gravity. The scale measures this normal force, so the reading will be higher than the person's actual weight (mass times gravitational acceleration).
Question 2: Which of the following chemical principles best explains why a mixture of oil and water separates into two distinct layers?
- Le Chatelier's Principle
- The Law of Conservation of Mass
- The principle of 'like dissolves like' (Correct answer)
- Avogadro's Law
Correct answer: The principle of 'like dissolves like'
The principle of 'like dissolves like' states that polar substances tend to dissolve in other polar substances, while nonpolar substances dissolve in other nonpolar substances. Water is a polar molecule, and oil is nonpolar. Due to this difference in polarity, they are immiscible and will not dissolve in each other, causing them to separate.
Question 3: In the process of photosynthesis, plants convert light energy into which type of energy for storage?
- Mechanical Energy
- Nuclear Energy
- Heat Energy
- Chemical Energy (Correct answer)
Correct answer: Chemical Energy
Photosynthesis is the process where green plants use sunlight to synthesize foods from carbon dioxide and water. The light energy is captured and used to convert these inorganic substances into glucose, an organic molecule. The energy is stored in the chemical bonds of the glucose molecule, which is a form of chemical energy.
Question 4: A scientist observes that a metal object rusts when exposed to air and moisture. This change is an example of a:
- Physical change
- Chemical change (Correct answer)
- Phase transition
- Nuclear reaction
Correct answer: Chemical change
Rusting, or the oxidation of iron, is a chemical change because a new substance (iron oxide) is formed. This new substance has different properties from the original iron. A physical change, like melting or boiling, does not result in the formation of a new substance.
Question 5: Which of the following is the primary function of mitochondria within a eukaryotic cell?
- To store genetic information
- To synthesize proteins
- To generate most of the cell's supply of adenosine triphosphate (ATP) (Correct answer)
- To control the passage of substances into and out of the cell
Correct answer: To generate most of the cell's supply of adenosine triphosphate (ATP)
Mitochondria are known as the 'powerhouses' of the cell. Their primary function is cellular respiration, a process that generates ATP, which is used as the main source of chemical energy to power the cell's biochemical reactions.
Question 6: Sound waves travel fastest through which of the following mediums?
- A solid steel beam (Correct answer)
- A vacuum
- Pure water
- The air at sea level
Correct answer: A solid steel beam
Sound waves are mechanical waves, meaning they require a medium to travel by causing vibrations in the particles of that medium. The speed of sound is fastest in solids, followed by liquids, and then gases, because the particles in a solid are packed more closely together, allowing vibrations to be transmitted more quickly. Sound cannot travel through a vacuum because there are no particles to vibrate.
OTEE - Officer Trainee Entrance General Science Principles Questions and Answers 1
An individual is standing on a scale in an elevator that is accelerating upwards.
How will the reading on the scale compare to their actual weight?