The distance travelled by an object in time $t$ is given by $s=(2.5) t^{2}$. The instantaneous speed of the object at $\mathrm{t}=5 \mathrm{~s}$ will be:
Solution
The distance traveled by an object in time $t$ is given by the equation $s = (2.5)t^2$. To find the instantaneous speed at a specific time, we need to find the first derivative of the distance function with respect to time, which gives us the velocity function:
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$v(t) = \frac{ds}{dt}$
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Differentiating the given equation with respect to $t$:
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$v(t) = \frac{d}{dt} (2.5)t^2 = 2(2.5)t = 5t$
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Now, we can find the instantaneous speed at $t = 5 \mathrm{~s}$ by plugging the value into the velocity function:
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$v(5) = 5(5) = 25 \mathrm{~m/s}$
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The instantaneous speed of the object at $t = 5 \mathrm{~s}$ is $25 \mathrm{~m/s}$.
About this question
Subject: Physics · Chapter: Kinematics · Topic: Motion in a Straight Line
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