Final answer:
At 35.0° north latitude, the deviation of a plumb bob from a radial line directed to the center of the Earth is due to the combination of gravitational force and centripetal acceleration caused by the Earth's rotation.
Step-by-step explanation:
The Earth's rotation causes a centripetal acceleration that, along with gravitational force, affects the direction in which a plumb bob hangs. At the poles, the situation is simpler since the centripetal acceleration approaches zero, and the plumb bob aligns with the gravitational force straight towards the center of the Earth. However, at other latitudes, this is not the case.
At 35.0° north latitude, the plumb bob will deviate slightly due to the Earth's rotation, aligning with the net force that is a combination of gravity and the centripetal acceleration. Since the centripetal acceleration is directed towards the Earth's axis of rotation, the plumb bob also points towards this direction and not directly to the center of the Earth.
Although the deviation is small and often negligible for everyday purposes, it is something that engineers account for, particularly when building very tall structures.
In conclusion, the plumb bob deviation at 35.0° north latitude is due to the vector sum of centripetal acceleration and gravitational force, causing the plumb bob to point slightly away from the Earth's center.