Unit 3 MCQ Bank

In a dry-friction problem, the friction force on a body acts:

At the point of impending motion, the friction force magnitude is:

For belt friction on a fixed drum, the tension ratio is given by:

At a smooth contact in a friction problem, which force component is absent?

The angle of friction φ is related to the coefficient of friction μ by:

The angle of repose is equal to:

For a ladder resting against a smooth vertical wall, the wall reaction is:

In the method of joints, the best joint to start with is usually one having:

At an unloaded joint where only two non-collinear members meet, those members are:

If a truss member is assumed to be in tension and the solved force comes out negative, the member is actually in:

In belt-friction notation, which side has the larger tension?

In the belt-friction formula T2/T1 = e^(μ θ), θ should be used in:

At an unloaded joint with three members, two of which are collinear, the third member is:

The unloaded-joint zero-force member rules cannot be used directly if:

For a 2D truss, a useful method-of-sections cut should generally pass through no more than how many unknown member forces?

When using the method of sections, why is it helpful to take moments about the intersection point of two unknown cut-member lines?

When analyzing a joint, truss member forces are usually assumed first as:

At a joint, a compressive member force acts:

In an ideal pin-jointed truss, members are modeled as:

In a ladder-friction problem, taking moments about the foot of the ladder eliminates:

Once a body is already sliding, the friction force is commonly modeled as:

If a block on an incline is just about to move up the plane, the friction force on the block acts:

If a block on an incline is just about to slide down, the friction force on the block acts:

At the wedge-block interface, the forces on the block and on the wedge are:

If a block is constrained by a smooth vertical guide, the guide exerts a reaction on the block that is:

For no slipping to occur, the resultant reaction at a contact must lie:

If the incline angle becomes greater than the angle of repose for a block, the block will:

For a cable carrying several concentrated vertical loads between supports, the horizontal component of tension is:

In a cable with varying segment slopes, the largest total tension is usually found in the segment that is:

In an ideal pin-jointed truss, external loads are assumed to act:

Why are support reactions usually found before applying the method of joints?

If a wedge is pushed to the right along a rough floor, the floor-friction force on the wedge acts:

If a wedge raises a block upward, the friction force on the block at the wedge contact acts:

For the same pair of dry surfaces, which statement is generally true?

If μ stays fixed but the wrap angle on a belt increases, the ratio Ttight/Tslack:

A truss joint analyzed by the method of joints is treated as a:

The method of sections is usually preferred over the method of joints when:

If a section cut passes through four unknown non-concurrent truss members in 2D, the isolated portion is usually:

Why must member angles or panel dimensions be known in truss analysis?

If you assume a friction direction on a free-body diagram and the solved friction value comes out negative, the correct interpretation is:

In the zero-force member rules, a support reaction acting at a joint should be treated as:

For a ladder against a smooth wall with only downward weights acting on it, the floor normal reaction equals:

When a person climbs a ladder resting against a smooth wall, the floor normal reaction becomes:

The minimum safe ladder angle is found from the condition:

For a block on an incline subjected to a horizontal push, the horizontal push should be resolved into components:

Why are Σ Fx = 0 and Sigma Fy = 0 usually sufficient at a pin-jointed truss joint?

Before applying the method of sections to a loaded truss, support reactions are usually needed because:

If the friction needed to maintain equilibrium comes out less than μ_s N, the correct conclusion is:

After making a section cut through a truss, the better side to analyze is usually the one with:

For a belt to remain without slipping on a drum, the actual tension ratio must be: