Physical Quantities and Measurement Test - 1

The metric system in weights and measures was adopted by the Indian Parliament in December 1956 with the Standards of Weights and Measures Act, which took effect beginning 1 October 1958. The Indian Coinage Act was passed in 1955 by the Government of India to introduce decimal coinage in the country.

Among the given units kilogram is the fundamental or base unit whereas others are the derived units. The kilogram (also kilogramme) is the base unit of mass in the metric system, formally the International System of Units (SI), having the unit symbol kg. It is a widely used measure in science, engineering, and commerce worldwide, and is often simply called a kilo in everyday speech.

Metre is the SI unit of length. The meter, symbol m, is the SI unit of length. It is defined by taking the fixed numerical value of the speed of light in vacuum c to be 299 792 458 when expressed in the unit m s^-1, where the second is defined in terms of Δν_Cs. The kilogram, symbol kg, is the SI unit of mass.

Mass is both a property of a physical body and a measure of its resistance to acceleration (a change in its state of motion) when a net force is applied. An object's mass also determines the strength of its gravitational attraction to other bodies. The basic SI unit of mass is the kilogram (kg).

Diameter of human hair is 50000nm. Electromagnetic radiation is measured in nanometers (one billionth of a meter, 1 × 10^-9 meters, or 0.000000001 meters). One human hair is approximately 50,000 nm in diameter.

Gram and kilogram are the units of mass whereas newton is the unit of weight (force). The unit of measurement for weight is that of force, which in the International System of Units (SI) is the newton. For example, an object with a mass of one kilogram has a weight of about 9.8 newtons on the surface of the Earth, and about one-sixth as much on the Moon.

The given relation is IqZ, since q=It

Expression is I²Zt

This is Electrical Power X time. Hence the unit is Joule.

Power is defined as the work done per unit time. So to get the SI unit of power:

Power=WorkTimePower= Work/Time

SI unit of Work  = Joules

SI unit of Time  = second

So S.I. unit of power = Joule/second = Watt