The British thermal unit (BTU or Btu) is a traditional unit of work equal to about 1055 joules. It is the amount of work needed to raise the temperature of one pound of water by one degree Fahrenheit (Physical analogue: one four-inch wooden kitchen match consumed completely generates approximately 1 BTU). BTU is the amount of heat required to raise the temperature of 1 avoirdupois pound of liquid water by 1 degree Fahrenheit at a constant pressure of one atmosphere. calorie, several definitions of the BTU exist, because the temperature response of water to heat energy is non-linear.
When an object free falls, it does not encounter a significant force of air resistance. Always Some Air Resistance. However, a falling object is going to run into some degree of air resistance. Air resistance is the outcome of collisions between the objectâs leading surface and air molecules. How much air resistance the object encounters depends on the speed the object is traveling and the cross sectional area of the object. When the object is falling faster, this increases air resistance.
There are four factors that affect the resistance of a wire: 1  Resistance is proportional to length. 2  Resistance is inversely proportional to cross-sectional-area.he resistance of an object is a measure of the how reluctant current is to flow through that object. It is given the symbol R and has the unit W (which is a greek letter omega and pronounced 'ohm').