Answer:
Explanation:
Required
The units of A and B
From the question, we understand that:
This implies that each of 
and 
will have the same unit as 
So, we have:
The unit of t is (s); So, the expression becomes
Divide both sides by 
Answer:
536,904 J/s
Explanation:
The energy output from motor is the input energy in the machine.
We know that efficiency is percentage energy ouput to energy input, and expressed as
Where n and E represent efficiency and energy respectively, subscripts o and i represent output and input respectively. Since for the machine we have the input energy then the output will be the product of efficiency and input energy
Energy output=0.6*1200 hp=720 hp
Converting hp to J/s we multiply by 745.7
Energy is 720*745.7=536,904 J/s
Answer: C. Steel
Explanation: When a sound wave travels through a solid body consisting
of an elastic material, the velocity of the wave is relatively
high. For instance, the velocity of a sound wave traveling
through steel (which is almost perfectly elastic) is about
5,060 meters per second. On the other hand, the velocity
of a sound wave traveling through an inelastic solid is
relatively low. So, for example, the velocity of a sound wave
traveling through lead (which is inelastic) is approximately
1,402 meters per second.
Answer:B.As the north pole of the electromagnet nears the south pole of the permanent magnet, the current reverses and the poles of the magnets then repel.
Explanation:
Even though humans share 100% of the same genes, the instructions contained within the genes are not entirely identical. Each person is unique. People have different hair colors, facial structures, and other traits. These differences between individuals result from very small differences in their DNA sequences. DNA also contains many so-called "housekeeping genes" that control important metabolic processes. As you will see, some of the differences in these genes can cause illness.
Although the DNA of any two people on Earth is, in fact, 99.9% identical, even a tiny difference can have a big effect if this difference is located in a critical gene.
