Projectile Motion Lab

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1. Set up the apparatus as shown.

   

2. As the marble is dropped into the top of the tube, it rolls down the ramp and becomes a projectile, following a parabolic trajectory, striking the floor at a distance d_x from the base of the table, and a distance d_y from the top of the table to the floor.
3. Write a procedure that will allow you to determine the initial velocity v_x of the marble as it exits the bottom of the tube horizontally. Be sure and release the marble at the top of the tube, and perform several trials to get an average. Keep track of your data, and show all calculations as part of your data analysis.
4. Now that you've measured an average value for the horizontal velocity of the marble as it exits the ramp, change the height of the ramp apparatus.
5. After measuring the new height, and knowing the horizontal velocity determined in step 3, calculate the horizontal landing distance d_x of the marble projected from this height.
6. After you've calculated the horizontal distance for this height, mark that distance on the paper on the floor with an X, and record the height from which the marble was projected beside that X.
7. Place a piece of carbon paper carbon side down over the X. Roll the marble to see how nearly it strikes the floor at your marked distance X. Record the actual horizontal landing distance.
8. Repeat steps 4-7 for a different height.

Projectile Motion Lab Quiz

1. The end of a ramp is placed at the edge of a table 1.1 m above the floor. A marble rolls off the ramp horizontally and strikes the floor a horizontal distance of 132 cm from the edge of the table.

(a) How long is the marble in the air before it strikes the floor?

(b) What is the initial horizontal velocity of the marble as it leaves the ramp?

2. The bottom of the ramp is raised to a height of 30 cm above the height of your table, and the marble has an initial horizontal speed of 90 cm/s as it leaves the edge of the ramp.

(a) How long will the marble remain in the air before it strikes the ground?

(b) How far horizontally will the marble strike the floor from the edge of the ramp?

(c) Just before the marble strikes the ground, what is the marble's

i. horizontal velocity v_x?

ii. vertical velocity v_y?

4. Suppose a marble is dropped from rest from the same height and the same time as a marble which is projected horizontally off the end of the ramp with an initial velocity of 80 cm/s.

Briefly explain which marble, the one dropped or the one projected,

(a) has the greater acceleration, and

(b) which marble will strike the floor first, neglecting air resistance.