it is also known as formula for circumfrence which is 2 times pi times radius. if radius was 5 then the circumfrence would be 10pi.
Answer:
Part a)
P = 13.93 kW
Part b)
R = 8357.6 Cents
Explanation:
Part A)
heat required to melt the aluminium is given by

here we have



Since this is the amount of aluminium per hour
so power required to melt is given by



Since the efficiency is 85% so actual power required will be

Part B)
Total energy consumed by the furnace for 30 hours



now the total cost of energy consumption is given as



Answer:

Explanation:
The change in potential energy can be expressed as:

where K is a constant with a value of
, q1 and q2 are the charges of the proton and the electron and r is the distance between them.
The charge for the proton is
and the charge for the electron is
.
Converting r=1.0nm to m:

Replacing values:


Answer:
Machine - A device consisting of fixed and moving parts that modifies mechanical energy and transmits it in a more useful form.
Mechanical advantage - Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system.
Inclined Plane - A plane set at an angle to the horizontal, especially a simple machine used to raise or lower a load by rolling or sliding.
Wedge - A piece of material, such as metal or wood, thick at one edge and tapered to a thin edge at the other for insertion in a narrow crevice, used for splitting, tightening, securing, or levering.
Screw - A cylindrical rod incised with one or more helical or advancing spiral threads, as a lead screw or worm screw.
Lever - A simple machine consisting of a rigid bar pivoted on a fixed point and used to transmit force, as in raising or moving a weight at one end by pushing down on the other.