Answer:
Position = 
behind the mirror
Nature = Virtual and Erect
Size = 
: Diminished
Explanation:
Sign convention-Distance measured to the left of pole is negative and to the right of pole is positive.
Object distance = u = -20 cm
Focal length = f = Radius of curvature/2 = 30/2 = 15 cm
We have to use mirror formula to find image distance.
Since the image distance is positive, it is formed behind the mirror or a virtual image is formed.
Magnification = 
Height of the object = 5 cm
Height of the image = 
Since the height of the image is positive and less than the size of object,it is erect and diminished.
It's Photoelectric Effect, I just a test with this same question. I am not good for explaining exactly how, but I was right.
Firstly, do you understand the concept of a wavelength?
V=IR
V=15x11
V=165ohms
I don’t quite remember the unit
Ohms law
Answer:
C.when the nucleus decays
Explanation:
In chemical reactions, the outermost electrons of atoms are re-arranged somehow without the involvement of the nuclei of the participating atoms of the elements.
Nuclear reactions causes changes within the atomic nucleus. For every atomic nucleus, a specific neutron/proton ratio ensures stability. When the stability ratio differs an atom becomes unstable and splits into one or more other nuclei with the emission of small particles of matter. This is what radioactivity entails.
