If P varies inversely as V and V varies directly as R2, find the relationship between P and R given that R = 7 when P = 2
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A.
P = 98R2 -
B.
PR2 = 98 -
C.
P = (frac{1}{98R2 -
D.
P = (frac{PR2}{98})
Correct Answer: Option B
Explanation
P = (frac{1}{v}) and vR2 = P = (frac{k}{v})……(i)
and v KR2 …….(ii)
(where k is constant)
Subst. for v in equation (i) = p = (frac{1^2}{KR})…..(ii)
when r = 7, p = 2
2 = (frac{k}{7^2})
k = 2 x 49
= 98
Subt. foe k in ….(iii)
P = (frac{98}{R^2})
PR2 = 98