The speedometer scale is 15 cm long and measures the vehicle speed from zero to 150 \frac{km}{h}. Find the speed of the speedometer indicator if the car is moving at an acceleration of 2 \frac{m}{s^2}.

Solutions of Savchenko Problems in Physics

Aliaksandr Melnichenka
October 2023

    <h3 id="back-link"><a href="/#1.2">$\leftarrow$Back</a></h3>

    <h3> Statement </h3>
    <p>
        $1.2.19.$ The speedometer scale is $15$ cm long and measures the vehicle speed from zero to $150$ $\frac{km}{h}$. Find the speed of the speedometer indicator if the car is moving at an acceleration of $2$ $\frac{m}{s^2}$.

    <h3>Solution</h3>
    <p>
        Equation for equal accelerated motion

$$150 \text{ km/h}=0 \text{ km/h}+at_n$$
Acceleration time from zero to full speed
$$t_n=20.83 \text{ s}$$
During this time, the speedometer arrow will travel the distance
$$15 \text{ sm}=ut_n$$
making the speed equal to
$$u=0.72 \text{ sm/s}$$

    <h4>Answer</h4>
    <p>
        $$v = 0.72 \text{ sm/s}$$
    </p>
    <p style="text-align: right; font-style: italic; font-size: 16;">Almaskhan Arsen</p>


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