++++ ++++ ++++ ++++ ++++
Concept Question
++++ ++++ ++++ ++++ ++++
kb
kc
kd
ke P3
P1
P2ka
u1
u2
u3
The work of the external forces in the spring
system of the ?gure is given by:
W = P
3
? U
3
(1)
W = P
3
? (U
1
+ U
2
+ U
3
) (2)
W = P
1
? U
1
+ P
2
? U
2
+ P
3
? U
3
(3)
? ++++ None of the above statements
? ++++ Statement (1)
? ++++ Statement (2)
? ++++ Statement (3)
? ++++ DKDU
++++ ++++ ++++ ++++ ++++
Answer
++++ ++++ ++++ ++++ ++++
The correct answer to the concept question
is: ++++
