Battering ram force

A battering ram weighing 400 g falls from a height of 3 m. Upon impact, the stake hits a depth of 60 cm. What is the average force overcoming the soil resistance?

Final Answer:

F =  20 N

Step-by-step explanation:

$$\begin{gathered} m=400\text{g}\to \text{kg}=400:1000\text{kg}=0.4\text{kg} \\ h=3\text{m} \\ s=60\text{cm}\to \text{m}=60:100\text{m}=0.6\text{m} \\ g=10{\text{m/s}}^2 \\ E=m\cdot g\cdot h=0.4\cdot 10\cdot 3=12\text{J} \\ E=W \\ W=E=F\cdot s \\ F=E/s=12/0.6=20\text{N} \end{gathered}$$

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