This is a physical change because cutting the string didn't change it chemically, but it did physically.
Answer:
You are exactly right. The molecules in hot air are moving faster than the molecules in cold air. Because of this, the molecules in hot air tend to be further apart on average, giving hot air a lower density. That means, for the same volume of air, hot air has fewer molecules and so it weighs less
I believe it’s 8.3 to be precise
Answer:
0.3405V
Explanation:
#Given a magnetic field of
, diameter= 18.5cm(r=9.25cm or 0.0925m), we find the magnetic flux of the loop as:
![\phi=B.(\pi r^2)cos 0\textdegree\\=1.9\pi\times 0.0925^2 \times cos 0\textdegree\\=5.107\times10^-^2 \ Tm^2](https://tex.z-dn.net/?f=%5Cphi%3DB.%28%5Cpi%20r%5E2%29cos%200%5Ctextdegree%5C%5C%3D1.9%5Cpi%5Ctimes%200.0925%5E2%20%5Ctimes%20cos%200%5Ctextdegree%5C%5C%3D5.107%5Ctimes10%5E-%5E2%20%5C%20Tm%5E2)
we can now calculate the induced emf,
:
![\frac{\phi}{\bigtriangleup t}=\frac{5.107\times 10^-^2}{0.15}\\=3.405\times 10^-^1V](https://tex.z-dn.net/?f=%5Cfrac%7B%5Cphi%7D%7B%5Cbigtriangleup%20t%7D%3D%5Cfrac%7B5.107%5Ctimes%2010%5E-%5E2%7D%7B0.15%7D%5C%5C%3D3.405%5Ctimes%2010%5E-%5E1V)
Hence, the induced emf of the loop is 0.3405V