Translational Motion Flashcards
What is the rules for adding vectors?
- Place the head of the first vector to the tail of the second vector
- Draw a line from the tail of the first vector to the head of the second vector
How is the magnitude of the SUM of two vectors determined?
Maximum: sum of the magnitudes of the two vectors
Minimum: difference of the magnitudes of the two vectors
What are the rules for subtracting vectors?
- Place the heads of the two vectors together
2. Draw a line from the tail of the first vector to the tail of the second vector
What characteristic defines component vectors?
Component vectors must be perpendicular to each other. Therefore, vectors that are obtuse to each other cannot be component vectors of a vector.
In a 30-60-90 triangle, what is the magnitude of the length of the side opposite of the smallest angle compared to the hypotenuse?
The hypotenuse is twice the length of the side opposite to the 30 degree angle.
How are angles approximated in a right triangle with sides of different lengths?
If a right triangle has sides of the different lengths, the angle being solved for cannot be 45 degrees. Therefore, the angle must either be greater or lesser than 45 degrees. If the length of the side opposite to the angle is greater than the side adjacent to the angle, the angle must be greater than 45 and less than 90. If the length of the side opposite to the angle is smaller than side adjacent to the angle, the angle must be less than 45 degrees.
see question 12 EK 1001
What is the difference between longitude and latitude?
Longitude runs north and south whereas latitude runs west and east
When a problem presents a right triangle, what is the first step to solving the magnitudes of the sides?
Graphical Estimation: If given one of the angles, the relative lengths of the sides can be determined. For example, if the angle given was less than 45 degrees, the length of that side opposite to that angle will be smaller than the side adjacent to that angle.
See TBR p.14
What is the graphical estimation technique?
The graphical estimation technique uses the angles of a right triangle to determined the relative lengths of the sides. If sides are of different lengths, the angle must be either greater or equal to 45 depending on the length of the side opposite to the angle.
Under constant acceleration, what is the equation for average velocity?
Average velocity can be calculated two ways:
- Change in displacement/change in time
- For constant acceleration: Initial velocity + final velocity / 2
A particle moves along a semicircular path at constant speed. What is the average acceleration? Can the average acceleration be nonzero even though the particle travels with constant speed?
The particle’s initial and final speed is the same, but the velocity is not since it is initially traveling up and finally traveling down. Therefore the initial velocity is positive whereas the final velocity is negative. Because average acceleration is the change in velocity over time, the change in velocity will be the difference between the positive and negative velocities which will give a nonzero average acceleration even though the particle travels with constant speed.
In what scenario can the average acceleration be nonzero when the particle is moving with constant speed?
Because acceleration is a vector, it takes into account magnitude and direction. If the magnitude does not change but the direction does, the particle can still possess an acceleration.
For a particle that moves in a CIRCULAR path, how does distance and displacement differ? How does speed and velocity differ?
A particle that moves in a circular path will have a displacement equal to the diameter of the circular path, whereas the distance will be equal to some length of the circumference.
Speed will differ from velocity because the distance differs from displacement. Speed is the change in distance divided by time whereas velocity is the displacement divided by time.
A particle at 5 m/s reverses it direction in 1 second to move at 5m/s in the opposite direction. If its acceleration is constant, what distance does it travel?
This problem is a simple matter of kinematics of objects traveling in air with an initial velocity, reaching its apex, then falling back to the ground. It can be solved by solving the displacement from the point when it launches with an initial velocity of 5m/s to its final velocity of 0m/s at its apex. The constant acceleration is given by calculating the change in velocity over time.Therefore, given the initial velocity, final velocity, acceleration, and time, displacement can be calculated for this interval. Once calculated, it can be multiplied by 2 to get total distance traveled.
Under constant acceleration, the graph of velocity vs. time can never look like what?
Parabola
