Test: Scientific Instruments - UPSC MCQ

The function of a spectrophotometer is (b) measuring light intensity. A spectrophotometer is an instrument used to measure the amount of light absorbed or transmitted by a substance at various wavelengths. It is commonly used in chemistry and biology to determine the concentration of a substance in a solution by measuring the intensity of light absorbed or transmitted by the sample.

The instrument used to measure atmospheric pressure is (c) barometer. A barometer is specifically designed to measure atmospheric pressure, which is the force exerted by the weight of the air in the atmosphere. It is often used in weather forecasting and can help indicate changes in weather patterns.

The instrument used to measure the intensity of earthquakes is (c) seismograph. A seismograph is a device that detects and records the vibrations caused by seismic waves, which are generated by earthquakes. It measures the intensity and duration of ground motion during an earthquake, providing valuable data for earthquake studies and monitoring.

The instrument used to measure the humidity in the air is (d) hygrometer. A hygrometer is specifically designed to measure the moisture content or relative humidity in the atmosphere. It is commonly used in meteorology, indoor climate control, and various scientific and industrial applications.

The purpose of an oscilloscope is (c) displaying electrical waveforms. An oscilloscope is an electronic instrument used to visualize and analyze the shape, frequency, and amplitude of electrical signals. It displays waveforms in a graphical representation, allowing users to observe and measure various characteristics of electrical signals.

The instrument used to measure electric current is (a) ammeter. An ammeter is specifically designed to measure the flow of electric current in a circuit. It is connected in series with the circuit and provides a direct measurement of the current passing through it.

The function of a theodolite is (b) measuring angles. A theodolite is a precise optical instrument used in surveying and engineering to measure horizontal and vertical angles. It consists of a telescope mounted on a base with graduated circles and leveling adjustments, allowing for accurate angular measurements.

The instrument used to measure the depth of the ocean is (c) sonar. Sonar (an acronym for "sound navigation and ranging") is a technique that uses sound waves to measure distances and map underwater objects. It is commonly used in oceanography and marine exploration to determine water depths and create detailed maps of the ocean floor.

The function of a Geiger-Muller counter is (a) measuring radiation levels. A Geiger-Muller counter is a radiation detection instrument that detects and measures ionizing radiation, such as alpha particles, beta particles, and gamma rays. It is commonly used in nuclear physics, radiation protection, and various industries where radiation monitoring is necessary.

The instrument used to measure the intensity of sound is (d) sound level meter. A sound level meter is specifically designed to measure the sound pressure level or intensity of sound waves in decibels (dB). It is commonly used in environmental noise monitoring, industrial hygiene, and acoustic research.

The purpose of a gas chromatograph is (b) measuring gas concentration. A gas chromatograph is an analytical instrument used to separate and analyze the components of a gas mixture. It utilizes the principle of gas chromatography, where the sample is vaporized and passed through a column to separate its components based on their different chemical properties. The gas concentration can then be determined by detecting the separated components.

The instrument used to measure the velocity of wind is (a) anemometer. An anemometer is specifically designed to measure the speed or velocity of wind. It usually consists of cups or propellers that rotate in response to the wind, and the rotation speed is used to calculate the wind speed.

The function of a hydrometer is (a) measuring the density of liquids. A hydrometer is an instrument used to measure the specific gravity or density of a liquid. It typically consists of a glass tube with a weighted bulb at one end that floats in the liquid. By measuring the depth to which the hydrometer sinks, the density or specific gravity of the liquid can be determined.

The instrument used to measure the temperature of an object without making physical contact is (c) pyrometer. A pyrometer is specifically designed to measure high temperatures without coming into direct contact with the object being measured. It operates based on the principle of detecting and measuring thermal radiation emitted by the object.

The purpose of a Geiger-Muller tube is (c) measuring radiation levels. A Geiger-Muller tube is the main component of a Geiger-Muller counter and is used to detect and measure ionizing radiation. The tube contains a gas-filled chamber that becomes ionized when radiation interacts with it, producing an electrical pulse that can be counted and measured.

The instrument used to measure the pH of a solution is (c) pH meter. A pH meter is specifically designed to measure the acidity or alkalinity of a solution by measuring its pH value. It consists of a glass electrode that generates an electrical potential proportional to the hydrogen ion concentration in the solution, allowing for accurate pH measurements.

The function of a refractometer is (c) measuring the refractive index of liquids. A refractometer is an optical instrument used to measure the extent to which light is bent or refracted as it passes through a liquid or transparent solid. By measuring the angle of refraction, the refractive index of the substance can be determined, which is often used to assess the composition or concentration of a solution.

The instrument used to measure the distance between two points is (b) rangefinder. A rangefinder is specifically designed to measure the distance between the instrument and a target object. It can use various techniques such as laser or optical systems to determine the distance accurately.

The purpose of a potentiometer is (c) measuring electrical potential difference. A potentiometer, also known as a voltage divider, is an electrical component used to measure and control electrical potential difference (voltage). It consists of a resistive element and a movable contact that can be adjusted to vary the output voltage.

The instrument used to measure the electric potential difference between two points in a circuit is (d) voltmeter. A voltmeter is specifically designed to measure the voltage or electric potential difference between two points in an electrical circuit. It is connected in parallel with the circuit and provides a direct measurement of the voltage across the chosen points.