A 10g mass placed on the pan of a spring balance causes an extension of 5cm. If a 15g mass is placed on the pan of the same spring balance, the extension is
A
3.3cm
B
6.5cm
C
7.5cm
D
10.8cm
E
15.0cm
Verified Correct Answer: C.
Physical Principles & Numerical Solution
F \(\alpha\) e and m \(\alpha\) F
\(\frac{m_1}{e_1}\) = \(\frac{m_2}{e_2}\)
\(\frac{10}{5}\) = \(\frac{15}{e_2}\)
e2 = 7.5cm
Source: Myschool Past Questions Archive (Record #28942)