QUIZ 3

Exercises and Problems from Conceptual Physics: Note that answers to odd numbered problems are  listed in the paperback supplement "Practicing Physics."

Ch 6

exercises

impulse

2

4

8

momentum

13

16

42

43 

44 

 

 

 

 

 

problems

impulse

2

3

 

momentum

6

7

9

 

 

 

 

 

 

Ch 7

review questions

10

exercises

15 (see fig 7.12)

20

21

28

30

48

50

54

 

 

 

 

 

 

problems

2

4

 5

 

 

 

 

 

 

 

 

Real Quiz 3

 

 Ch. 6

exercises

2.  large  time means small force...see fig 6.5..

4.    fig. 6.5
8. | Impulse | =  I = | change  in momentum | =  mv  = Ft  so that v = Ft/m.    Now, the force F  that kills a person and the mass m are fixed numbers.  The difference is the time t.         
13. momentum = mv. Does m change???
16. see fig. 6.11

 problems

2. mv = Ft.

 

6.  4m*(5 km/h) + m*(0) = 5m*V. Solve for V. See fig. 6.15

 Ch. 7

 exercises

21.  The direction of motion shown. It is NOT horizontal. The weight, of magnitude mg, points down. The two components of this downward vector are shown. One is along the motion.  This force component  does work on the object moving in that direction. The other is perpendicular to the component along motion. If the motion was horizontal, there would be NO component of gravitation force along the motion, and no work 

30.Same speed. On the the bottom track, as it goes down the middle dip, the second  ball  gains  more kinetic energy than the first ball,  but loses the same amount of kinetic energy  again after the leaving the dip.

54 .Momentum is conserved. See. Fig 6.15.  Kinetic energy is not conserved since the objects come to rest...

Problems

 See odd problems in the Supplement...