When the oil from a circular cylinder leaked, the formula for the spee

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QUESTION #4:

When the oil from a circular cylinder leaked, the formula for the speed of the leak is V = kh^2, where h was the height of the remaining oil and k was constant. If the height of the cylinder is 2, the speed of the leak is V’, When the height of the oil remaining is 4, what was the speed of the leak, in terms of V’?

A. 2V’
B. 4V’
C. V’/2
D. V’/4
E. V’

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suresh8055 · Answer

As Given 
V = kh^2

1. h=2 , V can be calculated as

V = Kh^2
V' =4k

2. h=4 ,

V =16k = 4(4k)= 4V'

Hence answer B !

kingjamesrules · Answer

The answer is B.

We know speed of the leak is V=4kh^2. (k is constant and h is height of oil remaining). Given - when height of the cylinder is 2 speed of leak is V'. Assuming height of oil in the cylinder is 2 = height of oil remaining, V' =K*2^2. or K=V'/4

Find V when height of oil remaining is 4. V=(V'/4)*4^2 = V'*4 or option B.

swanidhi · Answer

For a cylinder of height 2, that just starts leaking, h = 2. (Appears to be a typo in the question. 2 should be height of remaining oil)
 V` = 2^2k
V` = 4k

For a cylinder with remaining oil 4, h=4
 V = 4^2k = 16k

Thus,  V` = 4V

Answer B

Nightfury14 · Answer

V=Kh^2

at h=2; V'=K(2)^2=4K
=> K=V'/4 .... (I)

at h=4; V"=K(4)^2=16K .... (II)

substituting .. (I) into (II) , we have
V" = 16 (V'/4) =   4V'

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HKD1710 · Answer

Formula for the speed of leak is v = k*h^2. Let's write the question in terms of this formula:

"If the height of the cylinder is 2, the speed of the leak is V’" in terms for above formula can be stated as:

v' = k*2^2 (v' is the velocity when the hight is 2 )

v' = 4k

k = v'/4

"When the height of the oil remaining is 4, what was the speed of the leak" in terms of formula can be stated as:

v = k*4^2

v = 16k

v = 16*(v'/4)

v = 4v' (this is the velocity of leak in terms of v', when hight of remaining oil is 4)

Option  (B)  is correct.

Bunuel · Answer

MATH REVOLUTION OFFICIAL SOLUTION:

This type of question appears within a score range of 45 to 48. It is important to first find the value of a constant like this speed question. According to the question, when the height of the cylinder is 2, the speed of the leak is V’. Therefore, the first step would be: V’=k(2)^2=k4, k=V’/4. Because the question asks for the speed of the leak when the height is 4, the calculation would be: V=k(4)^2=(V’/4)(16)=V’/4. So, B is the correct answer.

bumpbot · Answer

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When the oil from a circular cylinder leaked, the formula for the spee

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