Answer:
a) The angular acceleration of the beam is 0.5 rad/s²CW (direction clockwise due the tangential acceleration is positive)
b) The acceleration of point A is 3.25 m/s²
The acceleration of point E is 0.75 m/s²
Explanation:
a) The relative acceleration of B with respect to D is equal:

Where
aB = absolute acceleration of point B = 2.5 j (m/s²)
aD = absolute acceleration of point D = 1.5 j (m/s²)
(aB/D)n = relative acceleration of point B respect to D (normal direction BD) = 0, no angular velocity of the beam
(aB/D)t = relative acceleration of point B respect to D (tangential direction BD)


We have that
(aB/D)t = BDα
Where α = acceleration of the beam
BDα = 1 m/s²
Where
BD = 2

b) The acceleration of point A is:

(aA/D)t = ADαj

The acceleration of point E is:
(aE/D)t = -EDαj

Answer:
<em>Angular displacement=68.25 rad</em>
Explanation:
<u>Circular Motion</u>
If the angular speed varies from ωo to ωf in a time t, then the angular acceleration is given by:

The angular displacement is given by:

The wheel decelerates from ωo=13.5 rad/s to ωf=6 rad/s in t=7 s, thus:



Thus, the angular displacement is:



Angular displacement=68.25 rad
Answer:
B. silicate rocks and metals
City 4 because it is closer to the equator