Question

http://imageshack.us/photo/my-images/192/page357.jpg/
I need help number 43) b Please!
the key is 180 rpm , 75 rpm

Answer 1

Hey I found your book online
http://www.caddomillsisd.org/100820818134650763/lib/100820818134650763/chap06.pdf
\[\text{1. If roller A turns counter-clockwise, roller B turns clockwise and roller C turns}\]
\[\text{ counterclockwise}\]

\[\text{2. for B, }3*120 = 2*x,\]
\[\omega_b = 180 rpm\]
\[\text{for C}\]
\[180*2 = \omega_c*4.8\]
\[\omega_c = 75rpm\]

Answer 2

how you get 120?

Answer 3

120 was given for the angular speed of gear A

Answer 4

180 rpm is the angular speed of B
75 is the angular speed of C

Answer 5

x was just a placeholder for \[\omega_b\]

Answer 6

2x?

Answer 7

2 was the radius of roller B

Answer 8

and how you get 4.8 ?

Answer 9

4.8 was the radius of roller C

Answer 10

It's all given in the picture at the bottom of page 357

Answer 11

ok, can you have me one more?

Answer 12

okay

Answer 13

Consider the tip of each hand of clock.find the linear velocity in milimmeter per second for each hand.
. Hours hand which 18 milimeter long

Answer 14

THe key is 0.003mm/s

Answer 15

That's in page 356. :-D one moment

Answer 16

you are the same my book

Answer 17

\[\text{Every hour, the hand moves }\frac{\pi}{6}rad\ => \omega_h = \frac{\pi}{6}\small{radh}^{-1}\]
multiply that by the length of the hour hand (18mm) to get the linear velocity of the hand

\[v_h = 3\pi\small{\frac{mm}{h}}\]

divide that by 3600 to get
\[\frac{\pi}{1200}\small\frac{mm}{s} \approx0.003 mm/s\]

Answer 18

you ar good job

Answer 19

how u get1200 ?

Answer 20

I divided 3pi by 3600 (the number of seconds in an hour) to convert it from mm/h to mm/s

Answer 21

and how u get 3p?

Answer 22

multiply pi/6 (angular speed of the hour hand in radians per hour) by 18 (length of the hour hand in millimeters)

Answer 23

ty,please! come back help, I have this home work every day

Answer 24

very, helpfull