Answer:
Explanation:
Assume both children bodies are point particles. The total moment of inertia about the rotation axis of 2 points particles of mass 16 kg and 25 kg at 1.5 m arm length is
where 
are the masses of 2 children 
are their distance to the center of rotation
(31-15 = 16).
Explanation:
the element phosphorus (P) has an atomic number of 15 and a mass number of 31. Therefore, an atom of phosphorus has 15 protons, 15 electrons, and 16 neutrons
A, b and d
Competition for fix resources of course increases the
energy expenditure needed to gather those resources and leaves less for a
given population. A lower amount of sunlight or water also contributes
to decreased energy which lowers growth. Finally, small borders limit
growth in that population density can only go so high before the death
rate increases beyond the birth rate.
Answer:
using the lens formula: 1/f = 1/u + 1/v
focal length f = -30 (negative because it is concave lens)
object distance u = 60
image distance v= unknown
1/-30 = 1/60 + 1/v
v = -20
So, the image is 20cm from lens (on the same side along with the object), and it is virtual (because of negative sign) and erect (concave lens must produce erect images).
