Define with unit 1) work done 2)power 3) sonar.
Answers
2) The rate of doing work is called power. Its SI unit is watt.
3) It is a device which is used to measure the depth of sea,ocean etc by sending waves and then receiving reflected waves.
Work done and energy transferred are measured in joules (J). The work done on an object can be calculated if the force and distance moved are known. A change in momentum happens when a force is applied to an object that is moving or is able to move. The total momentum in an explosion or collision stays the same.
ower is the rate (energy amount per time period) at which work is done or energy converted. The scientific unit of power is the watt (W), which is equal to one joule (energy amount) per second (time period). The PV Data Display shows electrical power units as kW, which is equal to one thousand watts.
Energy and power are often confused and used interchangeably. Quite often people will refer to the "power" generated by their PV panels today when they really mean the electrical energy produced during this time period.
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n physics, power is the rate of doing work, the amount of energy transferred per unit time. Having no direction, it is a scalar quantity. In the International System of Units, the unit of power is the joule per second (J/s), known as the watt in honour of James Watt, the eighteenth-century developer of the steam engine condenser. Another common and traditional measure is horsepower (comparing to the power of a horse). Being the rate of work, the equation for power can be written:
Sonar, short for Sound Navigation and Ranging, is helpful for exploring and mapping the ocean because sound waves travel farther in the water than do radar and light waves. NOAA scientists primarily use sonar to develop nautical charts, locate underwater hazards to navigation, search for and map objects on the seafloor such as shipwrecks, and map the seafloor itself. There are two types of sonar—active and passive.