Velocity function, unit vector notation, acceleration, speed

AI Thread Summary
The velocity vector function is defined as ~v = (6.0t - 4.0t^2)ˆi + 8.0ˆj + (3.0t)ˆk. To find the acceleration ~a at t = 3.0 s, the derivative of the velocity function with respect to time must be calculated, applying the rules of differentiation. The speed |~v| at t = 3.0 s can also be determined by evaluating the magnitude of the velocity vector at that time. The acceleration ~a will be zero when the derivative of the velocity function equals zero, which can be found by setting the acceleration equation to zero and solving for t. Understanding these principles allows for proper application of unit vector notation in solving the problem.
ColtonCM
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The problem:

The velocity ~v (vector notation, don't know how to type) is given by:

~v = (6.0t - 4.0t^2)ˆi + 8.0ˆj + (3.0t) with |~v| in meters per second and positive t seconds. ˆi, ˆj, ˆk have their usual meanings (unit vector notation).

(a) What is the acceleration ~a of the particle when t = 3.0 s?
(b) What is the speed of the particle |~v| at t = 3.0 s?
(c) If ever, when would the acceleration of the particle ~a be zero m/s^2?

I know what unit vector notation is and I know that acceleration is the derivative of velocity function and I know how to do the Calculus to obtain those things, but I don't know how what this function is when applied with unit vector notation? i refers to x-axis, j to y-axis, and k to z-axis. Am I allowed to take the derivative of each function to obtain acceleration, do I combine the functions, or in other words how do I handle this question?

Thanks for your time,

Colton Casados-Medve
 
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The rules of differentiation hold: the derivative of a sum is the sum of the derivatives, and the derivative of a function multiplied by a constant is the derivative multiplied by the constant. The unit vectors along the axes x, y, z are constants. If ##\vec V = X(t) \hat x + Y(t) \hat y + Z(t) \hat z ##
## \frac{d \vec V}{dt} = \frac{dX(t)}{dt} \hat x+ \frac{dY(t)}{dt} \hat y+ \frac{dZ(t)}{dt} \hat z ##
 
ehild said:
The rules of differentiation hold: the derivative of a sum is the sum of the derivatives, and the derivative of a function multiplied by a constant is the derivative multiplied by the constant. The unit vectors along the axes x, y, z are constants. If ##\vec V = X(t) \hat x + Y(t) \hat y + Z(t) \hat z ##
## \frac{d \vec V}{dt} = \frac{dX(t)}{dt} \hat x+ \frac{dY(t)}{dt} \hat y+ \frac{dZ(t)}{dt} \hat z ##

Got it, thanks a lot!
 
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