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The speed of a railway engine is 42 kilometres per hour, with no compartment attached to it. The speed of the engine reduces directly as the square root of the number of compartments attached to it. The speed of the engine is 24 kilometres per hour with 9 compartments attached. Find out the maximum number of compartments with which the engine can still move.
A49
B48
C46
D47
Answer: Option (Login/Signup)
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Solution:
Let Speed is the function of K1, K2 and n. K1 and K2 are constant and n is the no. of compartments.
Speed varies as,
S = K1 – (K2*(n)^1/2)
S = 42 when n= 0 and K1 = 42
S= 24 when n = 9 So K2 = 6
Now, S become,
S = 42 -6(n)^1/2 it must be > 0 (always).
So, n should be maximum which is less than 49, hence n = 48.
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Solution:
Let Speed is the function of K1, K2 and n. K1 and K2 are constant and n is the no. of compartments.
Speed varies as,
S = K1 – (K2*(n)^1/2)
S = 42 when n= 0 and K1 = 42
S= 24 when n = 9 So K2 = 6
Now, S become,
S = 42 -6(n)^1/2 it must be > 0 (always).
So, n should be maximum which is less than 49, hence n = 48.
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