SSC CGL 2024 Tier-I · 19 September 2024, Shift 1 · General Awareness · Question 13 of 100

Text as printed on a candidate's response sheet for this shift; answer per SSC's tentative key as marked on that sheet. Solution last reviewed 10 September 2026.

Where this paper and its answers come from

SSC does not publish CGL question papers or a public answer key. The questions and options here are reproduced as printed on a candidate's own response sheet for this shift — the Commission's text, unchanged. Each answer is SSC's tentative key as marked on that sheet; SSC allowed challenges to it and never publishes a final key. The solutions are written by UnlockIAS.

What was the name of the wind measuring instrument invented for the first time in 1450?

(a)Anemometer
(b)Ceiling Projector
(c)Transmissometer
(d)Dropsonde

Answer

Why

Correct — A. The anemometer is the instrument for wind, and the first known design is credited to Leon Battista Alberti in 1450.

Alberti's device was a disc hung so that the wind pushed it aside; the angle to which it swung read as the strength of the wind.

The name itself is the memory hook — Greek anemos, wind. Later designs are cup, vane and hot-wire, but they answer the same question the 1450 instrument did.

Why the others are wrong

(b)
Ceiling Projector — A ceiling projector throws a beam of light on to the cloud base so that its height can be worked out. It measures cloud ceiling, not wind.
(c)
Transmissometer — A transmissometer measures how much light survives a fixed path through the air, which yields visibility or runway visual range. It is a visibility instrument.
(d)
Dropsonde — A dropsonde is released from an aircraft and radios back readings as it falls through the atmosphere. It is a twentieth-century instrument and cannot be a 1450 invention.

Concept

Meteorological questions in SSC reduce to one table: the instrument, and the quantity it measures.

Wind speed goes to the anemometer and wind direction to the wind vane. Pressure goes to the barometer, humidity to the hygrometer, rainfall to the rain gauge, and temperature to the thermometer.

The common meteorological anemometer is the cup type, whose hemispherical cups spin faster as the wind rises, with the rate of rotation converted to a speed.

The date in the stem does most of the work. Three of the four names describe instruments that belong to the age of aviation and electronics, so only one can be from 1450.

Key facts

An anemometer measures wind speed, while a wind vane gives wind direction.
Leon Battista Alberti is credited with the first anemometer, in 1450.
The cup anemometer, with rotating hemispherical cups, is the common meteorological design.
A transmissometer measures atmospheric visibility and a ceiling projector measures cloud base height.

Study next

Meteorological instruments matched to the quantity each measuresUnits of wind speed and the Beaufort scaleAviation weather instruments such as the ceilometer and the radiosonde

Common traps

Reaching for the modern-sounding instrument when the question is anchored to 1450.
Confusing an anemometer with a wind vane, which gives direction and not speed.

SSC pairs an instrument or a record with the quantity behind it across shifts — the record produced by measuring an earthquake on 25 Sep 2024, 09:00, GA Q.2, and the unit of rainfall depth on 23 Sep 2024, 12:30, GA Q.13.

Related PYQs

No directly related past PYQ was found.