Would you really notice the change in gravitational pull or weight from the bottom of the Arch to the top? No

Yes

Explain why the aperture of the spherical mirror should be small compared to the radius of curvature of the mirror.

An object of dimensions 50 cm x 40 cm x 0.20 cm has a mass 60g. find its density in g/cm3 and kg/ m3

Atoms seldom exist as independent particles in nature a) as single particles, most atoms have low potential energy b) their electronegativity is much lower when they combine with other atoms c) atoms are more stable when they combine with other atoms d) neutral particles are rare