Calculate the efficiency of a hair dryer which takes in 3000J of energy per second and transfers 600J as useful heat energy. Calculate the efficiency of the hair dryer.

The efficiency of the hair dryer is 0.2 or 20%

Explanation:

The efficiency of a machine or any appliance is a measure of the useful work done by the machine when an effort is applied to the machine. The higher the efficiency of a machine, the more useful work the machine does.

Due to the economical and environmental impact of energy production, machines and appliances of high efficiency are being developed and recommended for domestic as well as industrial use nowadays.

In electrical appliances, energy is usually supplied by electrical power units. The higher the efficiency of an electrical appliance, the less power it consumes to do useful work. For a hair dryer which takes in 3000 J of energy per second and transfers 600 J of useful heat energy, its efficiency is calculated with formula below:

efficiency = useful energy / total energy input

Efficiency = 600 J / 3000 J = 0.2

Therefore, the efficiency of the hair dryer is 0.2 or 20%

step 1: initiation

initiation is the beginning of transcription. it occurs when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

step 2: elongation

elongation is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

step 3: termination

termination is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.

question: which statement best describes the different properties of metals?

answer: they are shiny and bend without breaking.

since metals have certain characteristics properties, they include the following: they are ductile, malleable, shiny, hard, lustrous, flexible and they are good conductor of heat and electricity. so therefore, metals are not dull and they are not non-flexible as listed. instead, they are shiny and flexible.

hope this , have a good day. c;