Match List I (Physical Quantity) with List II (SI Unit): A. Temperature; B. Weight; C. Mass; D. Pressure. List II: 1. Kelvin; 2. Kilogram; 3. Pascal; 4. Newton.
- (a)1 2 4 3
- (b)3 4 2 1
- (c)1 4 2 3
- (d)3 2 4 1
Correct — C, the order 1 4 2 3 (A-1, B-4, C-2, D-3). Temperature is measured in kelvin (1); weight is a force and so is measured in newton (4); mass is measured in kilogram (2); and pressure, being force per unit area, is measured in pascal (3). Reading A-B-C-D gives 1-4-2-3, which is option (c).
- (a)1 2 4 3 — This gets temperature right (1) but calls weight a kilogram (2) and mass a newton (4). Weight is a force (newton) and mass is measured in kilogram, so those two are swapped.
- (b)3 4 2 1 — This assigns pascal (3) to temperature and kelvin (1) to pressure — both wrong. Temperature is kelvin and pressure is pascal, so the ends are exchanged.
- (d)3 2 4 1 — This mislabels temperature as pascal (3), mass as newton (4) and pressure as kelvin (1); only weight would be near right. Three of the four pairings are wrong.
The SI system assigns each physical quantity a base or derived unit. Temperature has the base unit kelvin and mass the base unit kilogram; weight, being a force, uses the derived unit newton, and pressure, force per unit area, uses the derived unit pascal (1 Pa = 1 N/m^2).
The trap is the everyday habit of expressing weight in kilograms. In physics, weight is the gravitational force on a body and its unit is the newton, while mass (the amount of matter) is the kilogram. Separating force units (newton, pascal) from the base units (kelvin, kilogram) makes the match A-1, B-4, C-2, D-3.
- Temperature is measured in kelvin (K), an SI base unit.
- Mass is measured in kilogram (kg), an SI base unit.
- Weight is a force, measured in newton (N).
- Pressure is force per area, measured in pascal (Pa), where 1 Pa = 1 N/m^2.
Weight is a force (newton), not a kilogram; mass is the kilogram — giving 1 4 2 3.
- Expressing weight in kilograms instead of newtons.
- Confusing mass (kilogram) with weight (newton).
- Forgetting pressure's unit is derived from the newton.
NDA/UPSC match physical quantities to SI units — the weight-versus-mass (newton versus kilogram) distinction is the usual discriminator.
Match List I (Quantity) with List II (Units): I. High speed II. Wavelength III. Pressure IV. Energy; A) Mach B) Angstrom C) Pascal D) Joule.
- (a) I-B, II-A, III-C, IV-D
- (b) I-A, II-B, III-D, IV-C
- (c) I-A, II-B, III-C, IV-D
- (d) I-B, II-A, III-D, IV-C
Answer(c) I-A, II-B, III-C, IV-D
The same quantity-to-unit matching skill, and it also pairs pressure with the pascal — exactly the unit that decides this NDA question.
- practice — not a real PYQ
The SI unit of pressure is
- (a)Newton
- (b)Pascal
- (c)Joule
- (d)Watt
Answer(b) Pascal — pressure is force per unit area, 1 Pa = 1 N/m^2.
- practice — not a real PYQ
Which physical quantity has the newton as its SI unit?
- (a)Mass
- (b)Weight (force)
- (c)Temperature
- (d)Pressure
Answer(b) Weight (force) — weight is a force and is measured in newtons; mass is measured in kilograms.