UNITS AND MEASUREMENTS

Which of the following is a derived?

• temperature

• moles

• velocity

• current

Answer explanation

Velocity is a derived quantity as it involves both speed and direction, making it a vector quantity. Temperature, moles, and current are not derived quantities.

What SI unit is used to measure electric current?

• seconds

• amperes

• Kelvin

• mole

Answer explanation

Answer Explanation highlighting the correct choice: Electric current is measured in amperes (A), which is the SI unit for current

What is base quantities ?

• the branch of science concerned with the nature and properties of matter and energy

• the branch of science that deals with the identification of the substances of which matter is composed

• physical quantities that cannot be defined in terms of other physical quantities

Answer explanation

Base quantities are physical quantities that cannot be defined in terms of other physical quantities.

The unit m³ is used to express

• volume

• mass

• length

• density

Answer explanation

The unit m^3 is used to express volume, which is the amount of space occupied by an object or substance.

Which of the following pairs has the same dimensions?

• Specific Heat and Latent Heat

• Impulse and Momentum

• Surface Tension and Force

• Moment of Inertia and Torque

Answer explanation

Impulse and Momentum have the same dimensions as they are both measured in kg*m/s.

Dimensional formula of density is

• [M¹L²T⁰]

• [M¹L^-3T⁰]

• [M¹L¹T⁰]

Answer explanation

Density is mass per unit volume. The dimensional formula for density is [M^1L^-3T^0] as it represents mass (M) divided by volume (L^3) with no time component.

[M¹L¹T^-2] is dimensional formula for

• velocity

• Acceleration

• Force

• work

Answer explanation

The dimensional formula [M^1L^1T^-2] represents Force, as Force is defined as mass times acceleration, which corresponds to the given dimensions.

Which of the following is supplementary unit ?

• kelvin

• ampere

• radian

• joule

Answer explanation

The supplementary unit among the given options is radian, which is used to measure angles in a circle. Kelvin, ampere, and joule are not supplementary units.

The unit of plane angle is

• Steredian

• Radian

• Mol

• Candela

Answer explanation

The correct unit of plane angle is Radian, which is the angle subtended at the center of a circle by an arc equal in length to the radius of the circle.

Dimensions of Torque (Torque=Force X Radius) is

• none of these

Answer explanation

The correct answer is none of these because the dimensions of Torque are ML^2T^{-2}, not any of the provided options.