Explanation

• A voltmeter measures potential difference (voltage) between two points in a circuit.
• To do this correctly, it must be connected in parallel with the component across which the voltage is to be measured.

Last verified on 28-10-2026

Explanation

• An ammeter measures the electric current flowing through a circuit.
• It is connected in series so that the same current flowing through the circuit also passes through the ammeter.
• An ammeter has very low resistance to minimize its effect on the current being measured.

Additional information:

• A voltmeter, in contrast, is connected in parallel to measure the potential difference across a component.

Last verified on 28-10-2026

Explanation

• Freshwater is water that contains a very low amount of salt, typically less than 1% salinity.
• Examples of freshwater sources include rivers, lakes, streams, and underground aquifers.

Last verified on 28-10-2026

Explanation

• Water (H₂O) is a polar solvent due to its asymmetrical molecular structure.
• It results in a slightly positive charge on the hydrogen atoms.
• A slightly negative charge on the oxygen atom.

Last verified on 28-10-2026

Explanation

• Observation is the first step in the scientific method, which is used to solve biological problems.
• Scientists make observations about the natural world, notice patterns or phenomena, and ask questions about what they have observed.

The correct order of the scientific method is:

• Observation
• Question
• Hypothesis
• Prediction
• Experimentation
• Data analysis
• Conclusion

Last verified on 28-10-2026

Explanation

• Bronchitis is the inflammation of the bronchial tubes, which carry air to and from the lungs.
• It commonly causes coughing, mucus production, chest discomfort, and sometimes shortness of breath.
• Bronchitis may be acute, often caused by viruses, or chronic, commonly associated with long-term exposure to irritants such as cigarette smoke.

Last verified on 28-10-2026

Explanation

• The normal body temperature is: 37°C.
• The average normal body temperature is generally accepted as 98.6°F (37°C).
• A temperature over 100.4°F (38°C) means you have a fever.

Additional Information:

• Hypothermia is the term used for temperature less than 36.50°C.
• Mild Pyrexia is the term used for temperature (99-100°F).
• Moderate Pyrexia is the term used for temperature (100-103°F).
• Severe Pyrexia is the term used for temperature (103-105°F).

Explanation

• A pair of unlike parallel forces (forces that act in opposite directions) with different lines of force produce a couple.
• It is also known as a moment or torque.
• This is a rotational force that tends to cause rotation around a pivot point or axis.

Last verified on 26-10-2026

Explanation

• Water has maximum density at 4°C.
• When Water is in its Solid form (Ice) below 0°C.

Last verified on 27-10-2026

Explanation

• Frequency is the number of occurrences of a repeating event per unit of time.
• The SI unit of frequency is the hertz (Hz).
• 1 Hz = 1 cycle or vibration per second
• Unit: Hz = s⁻¹ (per second)
• Named after physicist Heinrich Hertz
• Used for waves, oscillations, sound, and electromagnetic radiation
• Derivations from other quantities: f = 1 / T
• Dimension T^−1