Answer:
From -15⁰ to 0⁰
H=mc¶
where H= heat absorbed or evolved
m=mass involved
c=specific heat capacity
¶=change in temperature
H=mc¶
Answer:
28
Explanation:
There is a 28 day cycle of the moon phase as it rotates on earths axis.
Answer:
New moment of inertia will be
Explanation:
It is given initially angular velocity 
Moment of inertia 
Angular momentum is equal to 
Now angular velocity is decreases to 
As we know that angular momentum is conserved
So 

So new moment of inertia will be 
The hot gases produce their own characteristic pattern of spectral lines, which remain fixed as the temperature increases moderately.
<h3><u>Explanation: </u></h3>
A continuous light spectrum emitted by excited atoms of a hot gas with dark spaces in between due to scattered light of specific wavelengths is termed as an atomic spectrum. A hot gas has excited electrons and produces an emission spectrum; the scattered light forming dark bands are called spectral lines.
Fraunhofer closely observed sunlight by expanding the spectrum and a huge number of dark spectral lines were seen. "Robert Bunsen and Gustav Kirchhoff" discovered that when certain chemicals were burnt using a Bunsen burner, atomic spectra with spectral lines were seen. Atomic spectral pattern is thus a unique characteristic of any gas and can be used to independently identify presence of elements.
The spectrum change does not depend greatly on increasing temperatures and hence no significant change is observed in the emitted spectrum with moderate increase in temperature.