Truck rail pressure

How much pressure on the rails will cause an empty truck weighing 20 tons if the contact area of all wheels and rails is 16 square centimeters?

Final Answer:

p =  125 MPa

Step-by-step explanation:

$$\begin{gathered} m=20\text{t}\to \text{kg}=20\cdot 1000\text{kg}=20000\text{kg} \\ S=16{\text{cm}}^2\to {\text{m}}^2=16:10000{\text{m}}^2=0.0016{\text{m}}^2 \\ g=10{\text{m/s}}^2 \\ F=m\cdot g=20000\cdot 10=200000\text{N} \\ {p}_0=\frac{F}{S}=\frac{200000}{0.0016}=125000000\text{Pa} \\ p=p_0/10^6=125000000/10^6=125\text{MPa} \end{gathered}$$

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