Answer:
Minerals must be solid, have an orderly atomic structure, have a recognized chemical composition, be naturally occurring and <u>inorganic in origin</u>.
Explanation:
At New Moon the percent illuminated is 0; at First and Last Quarters it is 50%; and at Full Moon it is 100%<span>. During the crescent phases the percent illuminated is between 0 and </span>50%<span> and during gibbous phases it is between </span>50%<span> and </span>100%<span>.
so it depends on the phase
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Answer:
Explanation:
According to newton's law , force between mass m₁ and m₂ at distance x is given by the following expression
F = G m₁m₂ / x²
differentiating F with respect to x , we have
dF / d x = ₋2G m₁m₂ / x³ .
Rate of reduction of force ∝ 1 / x³
Answer: 4/9π
Explanation:
Surfacearea of snowball(SA) =4πr^2
dSA/dT = - 10cm^2/min
d = 9, hence, r = 9/2 = 4.5
Taking the derivative of surface area with respect to time:
dSA/dT = 8πrdr/dt
dSA/dT = - 10, r = 4.5
-10 = 8π(4.5)dr/dt
-10 = 36πdr/dt
Make dr/dt subject of the formula
dr/dt = - 10/36π
d = 2r
Differentiating d with respect to time, 't'
dd/dt = 2dr/dt
Therefore, 2dr/dt = 2*(dr/dt)
2×(- 10/36π) = - 20/36π
= -4/9π
Therefore, rate by which diameter decreases when diameter is 9cm is
4/9 π
