- Home
- Standard 11
- Physics
13.Oscillations
hard
A mass $m$ attached to a spring oscillates with a period of $3\,s$. If the mass is increased by $1\,kg$ the period increases by $1\,s$. The initial mass $m$ is
A
$\frac{7}{9}\,kg$
B
$\frac{9}{7}\,kg$
C
$\frac{14}{7}\,kg$
D
$\frac{18}{7}\,kg$
Solution
$\frac{\mathrm{T}_{1}}{\mathrm{T}_{2}}=\sqrt{\frac{\mathrm{M}_{1}}{\mathrm{M}_{2}}}$
$\Rightarrow \frac{\mathrm{T}}{\mathrm{T}+1}=\sqrt{\frac{\mathrm{M}}{\mathrm{M}+1}}$
$\Rightarrow \frac{3}{4}=\sqrt{\frac{M}{M+1}}$
$\Rightarrow \frac{9}{16}=\frac{\mathrm{M}}{\mathrm{M}+1} \Rightarrow 9 \mathrm{M}+9=16 \mathrm{M}$
$\Rightarrow 7 \mathrm{M}=9 \Rightarrow \mathrm{M}=\frac{9}{7} \mathrm{Kg}$
Standard 11
Physics
Similar Questions
medium