Car

At what horizontal distance reaches the car weight m = 753 kg speed v = 74 km/h when the car engine develops a tensile force F = 3061 N. (Neglect resistance of the environment.)

Correct answer:

x =  52 m

Step-by-step explanation:

$$\begin{gathered} m=753\text{kg} \\ v=74\text{km/h}\to \text{m/s}=74:3.6\text{m/s}=20.55556\text{m/s} \\ F=3061\text{N} \\ F=ma \\ a=F/m=3061/753=\frac{3061}{753}\doteq 4.0651{\text{m/s}}^2 \\ v=at \\ t=v/a=20.5556/4.0651\doteq 5.0566\text{s} \\ x=\frac{1}{2}\cdot a\cdot t^2=\frac{1}{2}\cdot 4.0651\cdot 5.0566^2=52\text{m} \end{gathered}$$

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