Answer:

Explanation:
specific gravity of oil is 

we know that
change in pressure for oil is given as

here density and h is for oil

change in pressure for WATER is given as

here density is for water and h is for water

pressure change due to both is given as


Explanation:
It is given that,
Focal length of the concave mirror, f = -13.5 cm
Image distance, v = -37.5 cm (in front of mirror)
Let u is the object distance. It can be calculated using the mirror's formula as :



u = -21.09 cm
The magnification of the mirror is given by :


m = -1.77
So, the magnification produced by the mirror is (-1.77). Hence, this is the required solution.
Explanation:
You need two, maybe three things - something that's vibrating, a medium for those vibrations to propagate in, and a listener to hear it or recording equipment to pick it up
Answer:
Yes
Explanation:
The core of an electromagnet serves to stabilize the magnetic field created by the wire. The thicker the core, the more metal there is to amplify the current. Therefore, a thicker core does make an electromagnet stronger. Hope this helps!