Braking 83146

A car of mass m=1t moves at a speed v0=54 km/h. What braking force must be exerted to bring the car to a stop in 10 seconds, and how far will the car travel in this time?

Correct answer:

F =  1500 N

Step-by-step explanation:

$$\begin{gathered} m=1\text{t}\to \text{kg}=1\cdot 1000\text{kg}=1000\text{kg} \\ {v}_0=54\text{km/h}\to \text{m/s}=54:3.6\text{m/s}=15\text{m/s} \\ t=10\text{s} \\ {v}_0=a\cdot t \\ a=v_0/t=15/10=\frac{3}{2}=1.5{\text{m/s}}^2 \\ F=m\cdot a=1000\cdot 1.5=1500\text{N} \end{gathered}$$

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