Determine 12461

The 150t aircraft takes off at a speed of 288km/h and, after a while, reaches a speed of 900km/h. Determine the change in the kinetic energy of the aircraft.

Correct answer:

E =  4207.5 MJ

Step-by-step explanation:

$$\begin{gathered} m=150\text{t}\to \text{kg}=150\cdot 1000\text{kg}=150000\text{kg} \\ {v}_1=288\text{km/h}\to \text{m/s}=288:3.6\text{m/s}=80\text{m/s} \\ {v}_2=900\text{km/h}\to \text{m/s}=900:3.6\text{m/s}=250\text{m/s} \\ {E}_1=\frac{1}{2}\cdot m\cdot (v_2^2-v_1^2)=\frac{1}{2}\cdot 150000\cdot (250^2-80^2)=4207500000\text{J} \\ E=E_1/10^6=4207500000/10^6=\frac{8415}{2}\text{MJ}=4207.5\text{MJ} \end{gathered}$$

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