oldmidterm1 #1 - hinojosa (jlh3938) oldmidterm1 01 Turner...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: hinojosa (jlh3938) oldmidterm1 01 Turner (58185) 1 This print-out should have 20 questions. Multiple-choice questions may continue on the next column or page find all choices before answering. 001 10.0 points Consider a piece of string which is placed along the x-axis. Let m be the mass of a segment of the string and x the length of this segment. The linear mass density, , of a piece of string is defined as = m x . Denote to be its mass density defined as = mass volume and A its cross sectional area. Let us write = x A y . Using dimensional analysis, determine the equations which enable one to solve for x and y . 1. x = 1 , 2 y 3 x = 1 2. x = 1 , 3 x + 2 y = 1 3. x = 1 , 2 y + 3 x = 1 4. x = 1 , 2 y + 3 x = 1 5. x = 1 , 2 y 3 x = 1 6. x = 1 , 2 y 3 x = 1 7. x = 1 , 2 y 3 x = 1 8. x = 1 , 2 y 3 x = 1 correct 9. x = 1 , 3 x + 2 y = 1 10. x = 1 , 2 y 3 x = 1 Explanation: [ ] = [ x A y ] ML 1 = M x L 3 x L 2 y = M x L 2 y 3 x Equating both sides yields the equations x = 1 , 2 y 3 x = 1 002 10.0 points Two points in a rectangular coordinate sys- tem have the coordinates (4 . 6 cm, 5 . 9 cm) and ( 8 . 8 cm, 4 . 5 cm). Find the distance between these points. Correct answer: 13 . 4729 cm. Explanation: Given : x 1 = 4 . 6 cm , y 1 = 5 . 9 cm , x 2 = 8 . 8 cm , and y 2 = 4 . 5 cm . Using the Pythagorean Theorem, d = radicalBig ( x ) 2 + ( y ) 2 = radicalBig ( x 2 x 1 ) 2 + ( y 2 y 1 ) 2 = radicalBig [4 . 6 cm ( 8 . 8 cm)] 2 + (4 . 5 cm 5 . 9 cm) 2 = 13 . 4729 cm . 003 10.0 points Ann is driving down a street at 64 km / h. Suddenly a child runs into the street. If it takes Ann 0 . 718 s to react and apply the brakes, how far will she have moved before she begins to slow down? Correct answer: 12 . 7645 m. Explanation: d = v t = (64 km / h) (0 . 718 s) = 12 . 7645 m . Dimensional analysis for d : km h s 1 1 h 3600 s 1000 m 3600 km = m hinojosa (jlh3938) oldmidterm1 01 Turner (58185) 2 004 10.0 points The graph shows position as a function of time for two trains running on parallel tracks. At time t = 0 (origin) the position of both trains is 0. position time t B B A Which is true? 1. Both trains speed up all the time 2. Both trains have the same velocity at some time before t B correct 3. Somewhere before time t B , both trains have the same acceleration 4. At time t B , both trains have the same velocity 5. In the time interval from t =0 to t = t B , train B covers more distance than train A Explanation: The slope of the curve B is parallel to line A at some point t < t B ....
View Full Document

This note was uploaded on 03/26/2010 for the course PHY 303K taught by Professor Turner during the Fall '08 term at University of Texas at Austin.

Page1 / 10

oldmidterm1 #1 - hinojosa (jlh3938) oldmidterm1 01 Turner...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online