Final answer:
The maximum angle of inclination θ for which a block will remain stationary on an inclined plane, given a coefficient of static friction of 0.4, can be found using the arctangent function resulting in approximately 21.8 degrees.
Step-by-step explanation:
To find the maximum angle of inclination θ at which a block will remain stationary on an inclined surface, we can relate the coefficient of static friction (0.4 in this case) to the angle using the tangent function. When static friction has reached its maximum value, the block is on the verge of sliding, and the maximum force of static friction is equal to the component of the block's weight parallel to the incline. This force can be described by the equation μsN = mg sin(θ), where μs is the static friction coefficient, N is the normal force, m is the mass of the block, g is the acceleration due to gravity, and θ is the angle of inclination. Since the normal force is equal to mg cos(θ), substituting this into the equation and solving for θ gives us θ = tan-1(μs). Plugging in the given coefficient of static friction, the maximum angle θ can be found.
Using the given coefficient of 0.4, we can calculate the angle: θ = tan-1(0.4). Therefore, the maximum angle θ, for the block to remain stationary, is approximately 21.8 degrees.