Question

6. Certain reaulta from high school geometry are uaed repeatedly in Phyaica 1. A line makea an angle theta θ with the 2-axis. A pont along that line is indicated by a small, black dot Two daahed linea are alao drawn through the black dot. What ia the unknown angle labeled with a queation mark? Provide a brief argument that provea your anawer x-axis 7. It ia important to become familiar with phyaica terminology that will be uaed in the courae If two vectora are oriented at a 90-degree angle to each other, we aay they are perpendicular to each other or orthogonal. If two vectora point in the aame direction, we aay they are parallel to each other, even if they are not drawn aide-by-aide. If two vectora point in oppoaite directiona, we aay they are antiparallel. Complete the following aentencea with one word per blank. (Recall, the dot produot of two vectora: A.B- cosy, where the Greek gamma ia the angle between vector-A and vector-B.) a. If A. B ia a maximum, poaitive number, the vectora are b. If A. B ia a maximum. negative number, the vectora are o. If A. B equala zero the two veotora are d. A vector haa both length and direction. A vector'a length or magnitude ia a numbeir which may have a variety of unita. In phyaica, numbera are often called scalars. Fill in the blanka uaing some phyaica alliteration. Velocity ia a while speed ia a

Answer 1

From fig alpha = 180 - 90 - theta = 90 - theta Since alpha + beta = 90 degrees 90 - theta + beta = 90 degrees beta = theta a) parallel b) Anti parallel c) Orthogonal d) Velocity is a vector Speed is a Scalar