MCQ
Energy evolved in a chemical reaction:
- AConversion of mass into energy.
- ✓Conversion of bond energy into heat energy.
- CBoth $(a)$ and $(b).$
- DNeither $(a)$ nor $(b).$
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$x = 3\,sin\, 20\pi t + 4\, cos\, 20\pi t$ ,
where $x$ is in $cms$ and $t$ is in $seconds$ . The amplitude is ..... $cm$