Just learned this in chemistry. There are no subscripts, therefor each element only has 1 atom. Na has 1, O has 1 and H has one. There are 3 atoms.
Answer-3
A magnetic field is actually generated by a moving current (or moving electric charge specifically). The magnetic field generated by a moving current can be found by using the right hand rule, point your right thumb in the direction of current flow, then the wrap of your fingers will tell you what direction the magnetic field is. In the case of current traveling up a wire, the magnetic field generated will encircle the wire. Similarly electromagnets work by having a wire coil, and causing current to spin in a circle, generating a magnetic field perpendicular to the current flow (again right hand rule).
So if you were to take a permenant magnet and cut a hole in it then string a straight wire through it... my guess is nothing too interesting would happen. The two different magnetic fields might ineteract in a peculiar way, but nothing too fascinating, perhaps if you give me more context as to what you might think would happen or what made you come up with this question I could help.
Source: Bachelor's degree in Physics.
Answer:
(A) 140 j/sec (b) 1.26 K
Explanation:
We have given the heat heat flowing into the refrigerator = 40 J/sec
Work done = 40 W
(a) So the heat discharged from the refrigerator 
(b) Total heat absorbed =140 j/sec 
Let the temperature be 
Heat absorbed per hour =504000 ![[tex]=400\times 10^3\times \Delta T](https://tex.z-dn.net/?f=%5Btex%5D%3D400%5Ctimes%2010%5E3%5Ctimes%20%5CDelta%20T)
So 
Answer:
a. mechanical; require a medium to travel through
Explanation:
Longitudinal, transverse and surface waves are types of mechanical waves. For example, within the longitudinal waves are the sound waves, which needs a medium to propagate like the air. This is why sound does not travel in a vacuum.
And an example of a transverse wave is the waves that form in the water when a rock is thrown (ripples), these waves need a medium (the water) to propagate.
On the other hand, electromagnetic waves such as light waves do not need a medium to propagate, this is why we can see the light of distant stars because their light travels through the vacuum until it reaches us.
So, the answer is:
Transverse, surface, and longitudinal waves are all mechanical waves because they require a medium to travel through .
Answer:
Density is defined as:
Density = Mass/Volume
Now, density is an intensive property, this means that if you have 10 grams of a given material or 1000 grams of the same material, in both cases you will find the same density.
Then a roll of 50 pennies has the same density that a single penny.
The measures of a single penny are:
Mass = 2.5 g
Thickness = 1.52 mm
Radius = 9.525 mm
The coin is a cylinder, and the volume of a cylinder is:
V = pi*r^2*h
where:
pi = 3.14
r = radius = 9.525mm
h = thikness = 1.52mm
The volume is:
V = 3.14*(9.525mm)^2*1.52mm = 433.015 mm^3
The density will be:
D = 2.5g/433.015mm^3 = 0.00577 g/mm^3
