Question

In small-deflection approximations, the rotation angle (θ) of a rigid bar subjected to an external moment (M) can be represented by:

A. θ = M / (E * I)

B. θ = M / (L * G)

C. θ = M * L / (E * I)

D. θ = M * G / (L * I)

Answer 1

In Physics, particularly the study of rotational mechanics at the college level, the rotation angle (θ) of a rigid bar under an external moment (M) is correctly represented by θ = M * L / (E * I).

Step-by-step explanation:

The subject of this question is Physics, and it pertains specifically to the topic of rotational mechanics, which is typically covered at the college level. The question is about the small-deflection approximation which relates the rotation angle (θ) of a rigid bar, subjected to an external moment (M), to the physical properties of the bar and the material from which it is made. The correct representation of the rotation angle (θ) in terms of external moment (M), length of the bar (L), modulus of elasticity (E), and moment of inertia (I) would be option (C), which states that θ = M * L / (E * I). This formula is derived from the fundamental principles of how materials resist bending and the relationship between torque and angular deflection of an elastic body.