The Vector R(t) Is the Position Vector of a Particle $$\mathbf { r } ( \mathrm { t } ) = \sqrt { 3 } \mathrm { ti } + \left( \mathrm { t } + \frac { \pi } { 3 } \mathrm { t } ^ { 2 } \right) \mathbf { k }$$

question 17

Multiple Choice

The vector r(t) is the position vector of a particle at time t. Find the angle between the velocity and the acceleration vectors at time t = 0.
- $$\mathbf { r } ( \mathrm { t } ) = \sqrt { 3 } \mathrm { ti } + \left( \mathrm { t } + \frac { \pi } { 3 } \mathrm { t } ^ { 2 } \right) \mathbf { k }$$

• A) \(\frac { \pi } { 2 }\)
• B) 0
• C) \(\frac { \pi } { 3 }\)
• D) \(\pi\)

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Definitions:

Duration Recording

A method of behavioral observation that records the total time a specific behavior occurs within a given period.

Total Duration

The complete amount of time taken for a specific event or activity to occur from start to finish.

Duration Per Occurrence

A type of duration recording that involves recording the length of time per episode that a student engages in a target behavior.

Average Duration

A type of duration recording that produces only one number to graph. In this approach, the durations of each episode of a target behavior are added together and divided into the total number of times the behavior occurred.