Query 21 

course Phy 201

xêé®ßzåû–×Ëf蕾¥‹ÀlÊÄ”ŠŠåµ³“½Øassignment #021

Your work has been received. Please scroll through the document to see any inserted notes (inserted at the appropriate place in the document, in boldface) and a note at the end. The note at the end of the file will confirm that the file has been reviewed; be sure to read that note. If there is no note at the end, notify the instructor through the Submit Work form, and include the date of the posting to your access page.

¯öäz†aèýí¢þ˜k„f˜ŽiÃe™Ïή˜ÛF–î

Physics I

07-07-2007

......!!!!!!!!...................................

10:08:23

Explain how to obtain the final speed and direction of motion of a projectile which starts with known velocity in the horizontal direction and falls a known vertical distance, using the analysis of vertical and horizontal motion and vectors.

......!!!!!!!!...................................

RESPONSE -->

You can take the final and initial velocities and then find there difference and multiply by the motion to get the speed and then you can use cos and sin to find the direction.

.................................................

......!!!!!!!!...................................

10:09:09

** The horizontal velocity is unchanging so the horizontal component is always equal to the known initial horizontal velocity.

The vertical velocity starts at 0, with acceleration thru a known distance at 9.8 m/s^2 downward. The final vertical velocity is easily found using the fourth equation of motion.

We therefore know the x (horizontal) and y (vertical) components of the velocity. Using the Pythagorean Theorem and arctan (vy / vx) we find the speed and direction of the motion. **

......!!!!!!!!...................................

RESPONSE -->

I understand that the vertical velocity starts at 0, with acceleration thru a known distance at 9.8 m/s^2 downward. The final vertical velocity is easily found using the fourth equation of motion and therefore know the x (horizontal) and y (vertical) components of the velocity. Using the Pythagorean Theorem and arctan (vy / vx) we find the speed and direction of the motion

.................................................

......!!!!!!!!...................................

10:13:53

Give at least three examples of vector quantities for which we might wish to find the components from magnitude and direction. Explain the meaning of the magnitude and the direction of each, and explain the meaning of the vector components.

......!!!!!!!!...................................

RESPONSE -->

5,6 ; 7,8 ; 9,10 You would use the pythagorem therom to find the c2 component, then once you have the c component you have your magnitude and then you can take the sin and cos of the c^2 to find the direction of each vector quantity.

.................................................

......!!!!!!!!...................................

10:14:19

** GOOD STUDENT RESPONSE:

Examples might include:

A force acting on an object causing it to move in an angular direction.

A ball falling to the ground with a certain velocity and angle.

A two car collision; velocity and momentum are both vector quantities and both important for analyzing the collision..

The magnitude and directiohn of the relsultant is the velocity and direction of travel.

The vector components are the horizontal and vertical components that would produce the same effect as the resultant.

......!!!!!!!!...................................

RESPONSE -->

I understand that if a force acting on an object causing it to move in an angular direction.

A ball falling to the ground with a certain velocity and angle.

A two car collision; velocity and momentum are both vector quantities and both important for analyzing the collision..

The magnitude and directiohn of the relsultant is the velocity and direction of travel.

The vector components are the horizontal and vertical components that would produce the same effect as the resultant.

................................................."

&#

Good work. Let me know if you have questions. &#