Calc. the car's average acceleration

AI Thread Summary
To calculate the car's average acceleration, first identify the initial and final velocities as vectors: 25 m/s east and 25 m/s south. The change in velocity can be represented as a vector difference, requiring the use of trigonometry to determine the angle between the two directions. The average acceleration formula Aav = (Vf - Vi) / T can be applied, where T is the time interval of 15 seconds. Understanding vector components and using a coordinate system will aid in visualizing and solving the problem effectively. Properly outlining the problem on a set of axes is recommended for clarity.
hullio
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Help please :)

Homework Statement



A Car with a velocity of 25m/s[E] changes its velocity to 25m/s in 15s. Calc. the car's average acceleration.



Homework Equations



Aav= Vf - Vi / T

The Attempt at a Solution



I know that the angle is = to 45 degrees S of W since it's a right angle triangle and two sides are equal, therefore, 90 + 45 + 45 = 180.
 
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You are dealing with vectors here? Do you know how to express the formula you gave with vectors?
 
Yes dealing with vectors. Express the formula with vectors? I don't think so...? I've been learning all this Dx and Dy stuff in class. X-components, y-compenents, sin/cos/tan stuff.
 
Well X and Y components are the axis, or directions North is +Y, South is -Y, East is +X, West -X.

Just start by making a quick outline of the problem, on a set of axis, that always helps.
 
Are you familiar with this type of notation: \vec{r} = 34\vec{i} + 25\vec{j} (just an arbitrary vector... nothing to do with the problem... i denotes a unit vector in the x-direction... j denotes a unit vector in the y direction)
 
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