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(Copy only the key facts)(Have your HW out on your desk) A 10kg block being held at rest above the ground is released in freefall. At the instant that the block is 2.0 meters above the ground, the speed of the block is 2.5m/sec. The block was initially released at a height of how many meters?.
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(Copy only the key facts)(Have your HW out on your desk)A 10kg block being held at rest above the ground is released in freefall. At the instant that the block is 2.0 meters above the ground, the speed of the block is 2.5m/sec. The block was initially released at a height of how many meters? Do Now 09.21.10 Period 4 09.22.10
Homework Answers • t = 1.10 s, vf = 10.8 m/s • t = 5.10 s, d = 127.6 m • vf = 5,772 m/s • d = 19.6 m, vf = 19.6 m/s • vf = 13.6 m/s down, d = 7.6 m below
Objective • Combine vectors to find the resultant.
Vector • A quantity that shows magnitude and direction • Best represented with arrows 6 6 6 3 • Same direction, half the magnitude • Same magnitude, different direction
Adding Vectors • Tip to Tail Method Tip Resultant Vector Tail 1 2 3
Adding Vectors • Tip to Tail Method Tip Resultant Vector Tail 1 2 3
Adding Vectors • Mathematically 4 4 3 3 3 5 4 a2 + b2 = c2 32 + 42 = R2
Adding Vectors • A plane can travel 200 km/h. If it is heading south and has a 25 km/h tailwind also heading south, how fast and in what direction is it traveling?
Adding Vectors • The same plane can travel 200 km/h. If it is heading south and has a 50 km/h headwind blowing north, how fast is it traveling?
Adding Vectors • The same plane can travel 200 km/h. If it is heading south and has a 50 km/h crosswind blowing west, what is its velocity?
Adding Vectors • A river boat has a top speed of 12 m/s. If it attempts to cross a river with a current speed of 5 m/s, what will be its velocity?
Resolving into Components • Right triangle identities • Sine, Cosine, Tangent h o Θ a
Practice • A bullet is shot into the air with a velocity of 100 m/s at an angle of 45° above the horizontal. Find the horizontal and vertical velocities.