第9章仕事、エネルギー、単純機械Work, Energy, and Simple Machines原書 p.287–314

Key Equations重要な式

9.1 Work, Power, and the Work–Energy Theorem9.1 仕事、仕事率、仕事・エネルギー定理

work–energy theorem

仕事・エネルギー定理

power

仕事率

W = Δ KE = \frac{1}{2} m v_{2}^{2} - \frac{1}{2} m v_{1}^{2}

P = \frac{W}{t}

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conservation of energy

エネルギーの保存

K E_{1} + P E_{1} = K E_{2} + P E_{2}

ideal mechanical advantage (general)

理想的な機械的利得(一般)

ideal mechanical advantage (general)

I M A = \frac{F_{r}}{F_{e}} = \frac{d_{e}}{d_{r}}

ideal mechanical advantage (lever)

理想的な機械的利得(てこ)

ideal mechanical advantage (lever)

I M A = \frac{L_{e}}{L_{r}}

ideal mechanical advantage (wheel and axle)

理想的な機械的利得(輪軸)

ideal mechanical advantage (wheel and axle)

I M A = \frac{R}{r}

ideal mechanical advantage (inclined plane)

英語のヒント

理想的な機械的利得(斜面)

ideal mechanical advantage (inclined plane)

I M A = \frac{L}{h}

ideal mechanical advantage (wedge) $IMA = \frac{L}{t}$

理想的な機械的利得(くさび) $IMA = \frac{L}{t}$

ideal mechanical advantage (pulley)

理想的な機械的利得(滑車)

ideal mechanical advantage (pulley)

I M A = N

ideal mechanical advantage (screw)

理想的な機械的利得(ねじ)

I M A = \frac{2 π L}{P}

input work

入力の仕事

output work

出力の仕事

efficiency output

効率

W_{i} = F_{i} d_{i}

W_{o} = F_{o} d_{o}

% efficiency = \frac{W_{o}}{W_{i}} \times 100