Chapter 3: Projectile Motion

• Gravity, being a downward force, causes a projectile to accelerate in the downward direction.

• The force of gravity could never alter the horizontal velocity of an object since perpendicular components of motion are independent of each other; – vertical force does not effect a horizontal

motion.

–The result of a vertical force acting upon a horizontally-moving object is to cause the object to deviate from its

otherwise linear path

http://www.physicsclassroom.com/mmedia/vectors/hlp.html

http://www.physicsclassroom.com/mmedia/vectors/nhlp.html

Projectile Motion

Practice Problems pp. 664-665

1. Calculate the resultant velocity of Freda Flyer who normally flies at 100 km/h and then encounters a 10-km/h headwind(wind coming from ahead).

2. Calculate Freda Flyer’s speed in a 10-km/h tailwind(wind coming from behind).

The Truck and The Ball

• Imagine a pickup truck moving with a constant speed along a city street.

• In the course of its motion, a ball is projected straight upwards by a launcher located in the bed of the truck.

• What will be the path of the ball and where will it be located with respect to the pickup truck?

• http://www.physicsclassroom.com/mmedia/vectors/tb.html

Practice Problems pp. 664-665

12. A plane is flying at an altitude of 8000 m at a sped of 250 m/s. At what horizontal distance ahead of its target must a water balloon be released to strike the target on the ground(neglecting air resistance)?

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