<span>The acrylic plastic rod is 200 mm long and 15 mm in
diameter. If an axial load of 300 N is applied to it, determine
the change in its length and the change in its diameter.
. latd = -0.0002515 (15) = -0.00377 mm
elat = -Velong = -0.4(0.0006288) = -0.0002515
d = elong L = 0.0006288 (200) = 0.126 mm
elong = s
E = 1.697(106
)
2.70(109
) = 0.0006288
s = P
A = 300 p
4 (0.015)2 = 1.697 MPa
•3–25. T</span>
Answer:
, (before collision), (after collision).
Explanation:
The total momentum is obtained using the Principle of Momentum Conservation:
It is trivial to find that final speed and total momentum of the system are zero:
The total kinetic energy of the system becomes zero due to the inellastic collision and the same masses and speeds. Total kinetic energies before and after collision are, respectively:
Let's break the problem into two parts:
1) In the first part, the wheel starts with an angular speed
and it rotates with an angular acceleration of
for t=1.80 s. So we can find the total angle covered by the wheel in this part of the motion:
2) Now, the circuit breaker trips, so the wheel starts to decelerate with a certain angular acceleration
(which is negative). During this part of the motion, the wheel covered an angle of
.
3) So, we just need to add the angles the wheel covered in the two parts of the motion: