Question and Answers Forum

All Questions      Topic List

Others Questions

Previous in All Question      Next in All Question      

Previous in Others      Next in Others      

Question Number 16682 by tawa tawa last updated on 25/Jun/17

Answered by sandy_suhendra last updated on 25/Jun/17

$$\mathrm{F}=0.2\mathrm{N}$$$$\mathrm{\Delta }\mathrm{x}=1\mathrm{mm}={10}^{-3}\mathrm{m}$$$$\mathrm{k}=\frac{\mathrm{F}}{\mathrm{\Delta }\mathrm{x}}=\frac{0.2}{{10}^{-3}}=200\mathrm{N}/\mathrm{m}$$$$\mathrm{a})\mathrm{\Delta }\mathrm{x}=30\mathrm{mm}=0.03\mathrm{m}$$$$\mathrm{PE}\mathrm{the}\mathrm{spring}=\frac{1}{2}\mathrm{k}.\mathrm{\Delta }{\mathrm{x}}^2=\frac{1}{2}\times 200\times 0.{03}^2=0.09\mathrm{J}$$$$\mathrm{bi})\mathrm{KE}\mathrm{the}\mathrm{ball}=\mathrm{PE}\mathrm{the}\mathrm{spring}$$$$\frac{1}{2}{\mathrm{mv}}^2=0.09$$$$\frac{1}{2}\times 0.025\times {\mathrm{v}}^2=0.09$$$$\mathrm{v}=2.7\mathrm{m}/\mathrm{s}$$$$\mathrm{bii})\mathrm{A}=\mathrm{point}\mathrm{at}\mathrm{the}\mathrm{spring}$$$$\mathrm{B}=\mathrm{point}\mathrm{at}\mathrm{the}\mathrm{top}\mathrm{of}\mathrm{the}\mathrm{loop}$$$${\mathrm{KE}}_{\mathrm{A}}+{\mathrm{PE}}_{\mathrm{A}}={\mathrm{KE}}_{\mathrm{B}}+{\mathrm{PE}}_{\mathrm{B}}$$$$\frac{1}{2}\mathrm{m}.{\mathrm{v}}_{\mathrm{A}}^2+\mathrm{m}.\mathrm{g}.{\mathrm{h}}_{\mathrm{A}}=\frac{1}{2}\mathrm{m}.{\mathrm{v}}_{\mathrm{B}}^2+\mathrm{m}.\mathrm{g}.{\mathrm{h}}_{\mathrm{B}}$$$$\frac{1}{2}\times 2.7^2+0=\frac{1}{2}{\mathrm{v}}_{\mathrm{B}}^2+10\times 0.2$$$${\mathrm{v}}_{\mathrm{B}}^2=3.29\Rightarrow {\mathrm{v}}_{\mathrm{B}}=1.8\mathrm{m}/\mathrm{s}$$$$\mathrm{biii})\mathrm{N}={\mathrm{F}}_{\mathrm{sf}}-\mathrm{w}=\frac{\mathrm{m}.{\mathrm{v}}_{\mathrm{B}}^2}{\mathrm{R}}-\mathrm{m}.\mathrm{g}$$$$=\frac{0.025\times 1.8^2}{0.1}-0.025\times 10$$$$=0.56\mathrm{N}$$

Commented by tawa tawa last updated on 25/Jun/17

$$\mathrm{wow},\mathrm{God}\mathrm{bless}\mathrm{you}\mathrm{sir}.$$

Terms of Service

Privacy Policy

Contact: info@tinkutara.com