Question

Use dimensional analysis (i.e., examination of units) to determine if the following equation could be valid. So, “yes” or “no” and defend your answer.

                          v² = axt,

where v=speed, a=acceleration, x=displacement, t=time. (Hint: remember, all terms in an equation must have the same units.)

2. A bullet traveling horizontally with a speed of 35.0 m/sec hits a board perpendicular to the surface, passes through it, and emerges on the other side with a speed of 21.0 m/sec. If the board is 4.00 cm thick, what is the acceleration of the bullet? (A rough drawing may help.)

3. Fifty miles per hour is how many meters per second?

   (1 mi = 5280 ft., 1 m = 39.4 inches)

4. A displacement vector is 30.0 m at an angle of 37° to the horizontal.

What are the horizontal and vertical components of the displacement vector? (Hint: the vector can be thought of as the hypotenuse of a right triangle - use trig to find the sides.)

    

Answer 1