A) zero
B) 5 cm
C) 2.5cm
D) 1.25cm
Correct Answer: C
Solution :
\[{{m}_{1}}=10\text{ }g,\text{ }v=100\text{ }cm/s\] \[{{m}_{1}}+{{m}_{2}}=20\text{ }g,\text{ }h=?\] \[g=10\text{ }m/{{s}^{2}}=1000\text{ }cm/{{s}^{2}}\] From law of conservation of energy \[\frac{1}{2}m{{v}^{2}}=({{m}_{1}}+{{m}_{2}})gh\] \[\Rightarrow \] \[h=\frac{{{m}_{1}}v_{1}^{2}}{2({{m}_{1}}+{{m}_{2}})g}\] \[\therefore \] \[h=\frac{10\times 100\times 100}{2\times 20\times 1000}\] \[h=2.5\text{ }cm.\]You need to login to perform this action.
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