Monday, January 3, 2011


I.                OBJECTIVES:
a.      Describe projectile motion;
b.     Differentiate projectile motion from vertical andhorizontal motions;
c.      Solve problems on projectile motion; and
d.     Show appreciation through active participation in the class discussion.
A.    TOPIC:  Projectile Motion
B.    MATERIALS: Books (Physics), and visual aids.
C.    REFERENCE: Santos, Gil Nonato C. and Alfonso C. Danac.L-Physics (Investigatory Physics); Rex Bookstore Inc., Manila Philippines, 2006, pp.58-63.

-Demonstration              -lecture/discussion
Ask a student to roll a ball from the top of the table until it falls down to the floor. (Let other students observe.)

1. Let the students sketch the ball’s motion.
2. Describe the motion of the ball.
3. Why do you think the projectile path of the ball is parabolic?
4. Compare the motion of the ball from the horizontal and vertical motions.
5. Give the formulas for projectile motion and discuss each bysolving the following examples.
            a. A little girl throws her jackstone ball horizontally out of the window with a velocity of 30 m/s. If the window is 3m above the level, how far will the ball go before it hits the ground?
            b. A ball is thrown with an initial velocity of 4.47m/s at an angle of 66 above the horizontal. Find
            1. how long it takes the ball to land on the ground.
            2. how high the ball rises.
            3. the range.
            D. GENERALIZATION:
            Projectile motion is the combination of vertical and horizontal motions that are completely independent from each other. Projectile path is parabolic because of the pull of the gravity towards the object (projectile). As the object moves horizontally, the gravity pulls the object slowly downward until it falls to the ground. The two components of velocity are the Vy and Vx,with the Viy=0 as if the object is just dropped; Vix =Vicos =constant and Vy =Visin . The height is the vertical displacement and the range is the horizontal distance.

Directions: Solve the following problems. Showyour complete solutions.
1. Astone is thrown with an initial horizontal velocity of 10m/s from the top of the tower 200m high. Find the
a. distance after 2s.
b.time it hits the ground.

2. A player kicks the football from the ground level with a velocity of 27m/s at an angle of 30above the horizontal. Find the
            a. time the ball is in the air.
            c.maximum height

Directions: Solve the practice problems in your book on page 96.To be submitted

1 comment:

  1. I would like to borrow this item as a sample for my portfolio. Thank you po.