The position of a particle related to time is given by $x=\left(5 t^{2}-4 t+5\right) \mathrm{m}$. The magnitude of velocity of the particle at $t=2 s$ will be :
Solution
The position of a particle as a function of time is given by $x=\left(5 t^{2}-4 t+5\right) \mathrm{m}$. <br/><br/>To find the magnitude of the velocity of the particle at $t=2\,\mathrm{s}$, we first need to find the velocity of the particle as a function of time.
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The velocity $v$ is the time derivative of the position $x$:
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$v = \frac{dx}{dt}$
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Taking the derivative of $x$ with respect to $t$, we get:
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$v = \frac{dx}{dt} = 10t - 4\,\mathrm{m/s}$
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Now we can find the velocity of the particle at $t=2\,\mathrm{s}$ by plugging in $t=2$:
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$v(2\,\mathrm{s}) = 10(2) - 4\,\mathrm{m/s} = 16\,\mathrm{m/s}$
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Therefore, the magnitude of the velocity of the particle at $t=2\,\mathrm{s}$ is:
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$\boxed{|v(2\,\mathrm{s})| = 16\,\mathrm{m/s}}$
About this question
Subject: Physics · Chapter: Kinematics · Topic: Motion in a Straight Line
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