Questions: Given the velocity v=ds/dt and the initial position of a body moving along a coordinate line, find the body's position at time t.
v=9.8 t+7, s(0)=17
s(t)=
Transcript text: Given the velocity $\mathrm{v}=\frac{\mathrm{ds}}{\mathrm{dt}}$ and the initial position of a body moving along a coordinate line, find the body's position at time $t$.
\[
v=9.8 t+7, s(0)=17
\]
$s(t)=$ $\square$
Solution
Solution Steps
To find the body's position at time \( t \), we need to integrate the velocity function \( v(t) \) with respect to time \( t \). The initial position \( s(0) = 17 \) will be used to determine the constant of integration.
Solution Approach
Integrate the velocity function \( v(t) = 9.8t + 7 \) to find the position function \( s(t) \).
Use the initial condition \( s(0) = 17 \) to solve for the constant of integration.
Substitute the constant back into the position function to get the final expression for \( s(t) \).
Step 1: Define the Velocity Function
The velocity of the body is given by the equation:
\[
v(t) = 9.8t + 7
\]
Step 2: Integrate the Velocity Function
To find the position function \( s(t) \), we integrate the velocity function:
\[
s(t) = \int v(t) \, dt = \int (9.8t + 7) \, dt = 4.9t^2 + 7t + C
\]
where \( C \) is the constant of integration.
Step 3: Apply the Initial Condition
We know the initial position \( s(0) = 17 \). Substituting \( t = 0 \) into the position function gives:
\[
s(0) = 4.9(0)^2 + 7(0) + C = C
\]
Setting this equal to the initial position:
\[
C = 17
\]
Step 4: Write the Final Position Function
Substituting \( C \) back into the position function, we have:
\[
s(t) = 4.9t^2 + 7t + 17
\]
Final Answer
The position of the body at time \( t \) is given by:
\[
\boxed{s(t) = 4.9t^2 + 7t + 17}
\]