Vectors Solving Mathematically Vectors If two vectors are

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Vectors Solving Mathematically

Vectors Solving Mathematically

Vectors If two vectors are arranged at 90º, we can use mathematics to make

Vectors If two vectors are arranged at 90º, we can use mathematics to make our lives somewhat easier. For example: A student walks 30 m north than 40 m east. What is the students displacement?

Vectors Make a “sketch” of the problem. This does not need to be made

Vectors Make a “sketch” of the problem. This does not need to be made to scale. It is only for your reference. 40 m Looking at our sketch we see our two vectors make a right triangle. 90º 30 m R=? This allows us to us the Pythagorean Theorem and SOH CAH TOA to solve.

Vectors Procedure: 1) Write equation. 40 m a 2 + b 2 = c

Vectors Procedure: 1) Write equation. 40 m a 2 + b 2 = c 2 2) Sub in with units. (30 m)2 + (40 m)2 = c 2 30 m Θ R = 50 m 3) Solve in with units. c = 50 m However, we are not done. Since vectors have magnitude and direction, we must include a direction.

Vectors Procedure to find Direction: 1) Write an equation. 40 m (opp) tan Θ

Vectors Procedure to find Direction: 1) Write an equation. 40 m (opp) tan Θ = opp / adj 2) Sub in with units. tan Θ = 40 m / 30 m (adj) Θ R = 50 m 3) Solve in with units. Θ = 31º Now we have both magnitude and direction, so we can properly call out the displacement.

Vectors 40 m 30 m Θ = 31º R = 50 m Displacement (R)

Vectors 40 m 30 m Θ = 31º R = 50 m Displacement (R) = 50 m @ 31º east of north

Vectors Note the procedure described in the previous example. To receive full credit on

Vectors Note the procedure described in the previous example. To receive full credit on short answer questions you must perform the following steps: 1) Write an equation. 2) Sub in with units. 3) Solve in with units.