A force of 100N stretches an elastic string to a total length of 20cm. If...

JAMB 1985

A force of 100N stretches an elastic string to a total length of 20cm. If an additional force of 100N stretches the string 5cm further, Find the natural length of the string

A. 15cm
B. 12cm
C. 10cm
D. 8cm
E. 5cm

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Correct Answer: Option A

Explanation

Using, f₁ = f₂

e₁ = 20 - L ; e_{2 = 5cm

\(\frac{f_1}{e_1}\) = \(\frac{f_2}{e_2}\)

\(\frac{100}{20 - L}\) = \(\frac{100}{5}\)

hence, L = 15cm}

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A force of 100N stretches an elastic string to a total length of 20cm. If...

Correct Answer: Option A

Explanation

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