Spring 2005

HOMOKINETICS II

PRACTICE PROBLEMS II

ANSWER SHEET

 

1.      a= w2-w1           1.1 rad/s – 1 rad/s       a= 3.333 rad/s2     

                        t                        .03 s

 

2.   v= wr     6m/s=12 rad/s x r         6m/s=    12 rad/s x r           r= 6 m/s       r=0.5 m

                                                        12 rad/s    12 rad/s                   12 rad/s

 

3.      0=v12 + 2ad

0 =(22 sin 20 m/s)2 + (2)(-9.81 m/s2)d

(19.62 m/s2)d = 56.62 m2/s2

d= 56.62 m2/s2

      19.62 m/s2

      

       d=2.89 m

 

      0=v1 + 2at

0 =(22 sin 20 m/s) + (-9.81 m/s2)t

(9.81 m/s2)t= 7.52 m/s2

t= 7.52 m/s2

      9.81 m/s2

 

      t=.767 s

 

       t=(0.767 x 2)

       t= 1.53 s

     

      dh = vht

      dh =(22 cos 20 m/s) (1.53 s)

      dh =31.63 m

 

4. dh = vht

      dh =(6 m/s) (0.7 s)

      dh =4.2 m

 

5. a= w2-w1           400 deg/s – 250 deg/s       a= 500 deg/s2     

                      t                        .3 s

 

6. a= w2-w1           200 deg/s2 =  w2          w2 =200 deg/s2  x .4 s

                      t                                 .4 s

 

    w2 =80 deg/s

 

 

   

 

7. f = 1.75 rev x 360 deg

       f = 630 deg

 

       q = 360 deg x .25

       q = 90 deg

4.         0 = v21 + 2ad