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Solve this : Mods And StarsA car starts from rest and moves along the x-axis with constant acceleration of 5 m/s² for 8 seconds. If it then continues with constant velocity, what distance will the car cover in 12 seconds since it started from the rest? |
Answer» <html><body><h2>Given:</h2><p> A <a href="https://interviewquestions.tuteehub.com/tag/car-909011" style="font-weight:bold;" target="_blank" title="Click to know more about CAR">CAR</a> starts from rest and moves along the x-axis with a constant <a href="https://interviewquestions.tuteehub.com/tag/acceleration-13745" style="font-weight:bold;" target="_blank" title="Click to know more about ACCELERATION">ACCELERATION</a> of <a href="https://interviewquestions.tuteehub.com/tag/5-319454" style="font-weight:bold;" target="_blank" title="Click to know more about 5">5</a> m/s² for 8 seconds.</p><p></p><h2>To Find: </h2><p>what distance will the car cover in 12 seconds since it started from rest.</p><p></p><h2>Solution:</h2><p>We know that,</p><p><img align="absmiddle" alt="s = ut + \frac{1}{2}at^{2}" class="latex-formula" id="TexFormula1" src="https://tex.z-dn.net/?f=s%20%3D%20ut%20%2B%20%20%5Cfrac%7B1%7D%7B2%7Dat%5E%7B2%7D%20" title="s = ut + \frac{1}{2}at^{2}"/></p><p>But given that, the initial velocity is zero. Therefore, the distance covered by the car in first 8 seconds is </p><p><img align="absmiddle" alt="s = 0 + \frac{1}{5} \times 5 \times {8}^{2}" class="latex-formula" id="TexFormula2" src="https://tex.z-dn.net/?f=s%20%3D%200%20%2B%20%20%5Cfrac%7B1%7D%7B5%7D%20%20%5Ctimes%205%20%5Ctimes%20%20%7B8%7D%5E%7B2%7D%20" title="s = 0 + \frac{1}{5} \times 5 \times {8}^{2}"/></p><p>s = 180 metres</p><p></p><p>Therefore, the velocity <a href="https://interviewquestions.tuteehub.com/tag/attained-7662680" style="font-weight:bold;" target="_blank" title="Click to know more about ATTAINED">ATTAINED</a> at the end of 8 seconds is:</p><p>from, v = u + at</p><p>=>V= 0 + 5 x 8 40 m/s </p><p>Therefore, since the car has moved with constant velocity from 8th second to 12 second, the distance travelled is </p><p>S = v × t = 40 x 4 = <a href="https://interviewquestions.tuteehub.com/tag/160-277205" style="font-weight:bold;" target="_blank" title="Click to know more about 160">160</a> m.</p><p></p><h2>Therefore, the total distance travelled is 160 + 160 = <strong><u>320m.</u></strong></h2><p></p><h3>Hope it helps :)</h3></body></html> | |