Question

Multiple choice Questions:

1) A simple (but incomplete) definition of a/an______ is that it is a mathematical entity that has a specific magnitude and direction.

A. director B. aviator C. bisector D. scalar E. vector

2) It is a physical quantity expressible by a single real number whose value is independent of the coordinate system (of ordinary physical space). A ________can have a direction in an abstract space. For example, temperature on the Celsius scale: it can have positive or negative value. But many_________ quantities only have positive values like temperature on the Kelvin scale. A__________ can be regarded as a one-dimensional vector with the one-direction being in an abstract space, but in the usual way of speaking one would say it is NOT a vector.

A. director B. aviator C. bisector D. scalar E. vector

3)Vector components are computed by multiplying the magnitude (or length) of a vector by the cosines of the angles the vector makes with the positive coordinate directions of a:

A. circle B. coordinate system C. rotation D. square E. wheel

4) The components of multi-dimensional physical vectors:

A. are unique

B. can be chosen only two ways: the two ways will lead to different physical behavior

C. can be chosen in infinitely many ways: each way leads to a different physical behavior

D. can be chosen in infinitely many ways. However, the physics of the vector remains the same and in any problem the choice of components (i.e., the choice of a coordinate system) is arbitrary. But some choices make the problem a lot easier.

E. cannot be determined at all in principle

5) A vector of magnitude 20 is added to a vector of magnitude 25. The magnitude of this sum might be:

A.zero B.3 C.12 D.47 E.50

6) For general vectors A and B, the dot product A · B equals:

A) B · B

B) A · A

C) A · B^2

D) A^2 · B

7) A man walks 40 m on level ground to an elevator and then rises 70 m. What approximately is the magnitude of his displacement from the starting point?

A. 8m B. 110m C. 30m D. 6500m E. 80m

8) The eye of a hurricane passes over Bermuda moving 20.0 ◦ north of west at 40 km/h for 2 hours and then turns due north moving at 20 km/h. What is its displacement relative to Bermuda after 4 hours being at Bermuda: give distance from Bermuda and angle relative to north? Neglect the curvature of the Earth.

Answer 1