Question about notation in physics

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The discussion centers on finding the velocity and position of a particle with an initial velocity of 5i m/s and a varying acceleration of a = 6√t j. The participant integrated the acceleration to determine velocity and then integrated the velocity to find position. There is a question about whether to include the vector notation (arrow) when expressing these equations as functions of time. It is confirmed that vector notation should be used, and the inclusion of unit vectors i and j is necessary for clarity. The final conclusion emphasizes that both sides of the equation must maintain vector representation.
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So it says that a particle is going with a velocity of 5i m/s at t = 0 and varying acceleration a = 6√t j.
it asked me to find the velocity and position of the particle as a function of time.
So i did an integral of the acceleration to get velocity and did the integral of the velocity to get the position. I was wondering whenever i write the equation as a function of time, do i still need that arrow (→ ) on top of the v for vector and r for position?
 
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monac said:
So it says that a particle is going with a velocity of 5i m/s at t = 0 and varying acceleration a = 6√t j.
it asked me to find the velocity and position of the particle as a function of time.
So i did an integral of the acceleration to get velocity and did the integral of the velocity to get the position. I was wondering whenever i write the equation as a function of time, do i still need that arrow (→ ) on top of the v for vector and r for position?
If it's a vector, then yes, we usually put the arrow above the variable.

\vec{r}(t) = x(t)\hat{i}+t(t)\hat{j}+z(t)\hat{k}
 
SammyS said:
If it's a vector, then yes, we usually put the arrow above the variable.

\vec{r}(t) = x(t)\hat{i}+t(t)\hat{j}+z(t)\hat{k}

so if I solved the integral and I got like
r(t) = 8t^2 + 5t
I put the arrow on top of the arrow since it's a vector. I get that ...
But do I still include the i and j?
so would it be r(t) = 8t^2 i + 5t j ?
 
monac said:
so if I solved the integral and I got like
r(t) = 8t^2 + 5t
I put the arrow on top of the arrow since it's a vector. I get that ...
But do I still include the i and j?
so would it be r(t) = 8t^2 i + 5t j ?
Yes, use the \hat{i} & \hat{j}\,.

If the left side of an equation is a vector, then the right side must also be a vector.
 
Thank you! :)
 
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