Online Engineering Mechanics Test - Engineering Mechanics Test - Random

The gusset plate G of a bridge joint is subjected to the two member forces at A and B. If the force at B is horizontal and the force at A is directed at = 30°, determine the magnitude and direction of the resultant force.

Determine the magnitude of the x and y components of the 2—kN force.

Determine the force in each strut and tell whether it is in tension or compression.

Determine the magnitude of the projection of the moment cause by the force about the aa axis.

Determine the couple moment. Use a vector analysis and express the result as a Cartesian vector.

Determine the moment of force F₃ about point A on the beam.

If the boom in the previous problem is to remain horizontal when the stone S is removed, what is x?

A tower used in an electrical substation supports a power line which exerts a horizontal tension of T = 500 lb on each side truss of the tower as shown. Determine the force in members BC, CM, and LM of a side truss and indicate whether the members are in tension or compression.

The floor beams AB and BC are stiffened using the two tie rods CD and AD. Determine the force along each rod. Assume the three contacting members at B are smooth and the joints at A, C, and D are pins.

Determine the magnitude of the forces in pins B and D of the four-member frame.

A force of 500 N acts at the top of the two-member frame. If the members are in smooth contact with one another at A, B, and C with no fasteners, determine the shear force developed at a horizontal section through point D of the support. Also, what are the axial force, shear force and moment at point E?

Locate the center of gravity of the volume generated by revolving the shaded area about the z axis. The material is homogeneous.

A boy twirls a 15-lb bucket of water in a vertical circle. If the radius of curvature of the path is 4 ft, determine the minimum speed the bucket must have when it is overhead at A so no water spills out.

A girl having a weight of 40 lb slides down the smooth slide onto the surface of a 20-lb wagon. Determine the speed of the wagon at the instant the girl stops sliding on it. If someone ties the wagon to the slide at B, determine the horizontal impulse the girl will exert at C in order to stop her motion. Neglect friction and assume that the girl starts from rest at the top of the slide, A.

The two blocks A and B each have a mass of 500 g. The blocks are fixed to the horizontal rods and their initial velocity is 2 m/s in the direction shown. If a couple moment of M = 0.8 N • m is applied about CD of the frame, determine the speed of the block in 4 s. The mass of the supporting frame is negligible and its free to rotate about CD.

At the instant shown, gear A is rotating with a constant angular velocity of _A = 6 rad/s. Determine the largest angular velocity of gear B and the maximum speed of point C.

The rotation of link AB creates an oscillating movement of gear F. If AB has an angular velocity of _AB = 8 rad/s, determine the angular velocity of gear F at the instant shown. Gear E is a part of arm CD and pinned at D to a fixed point.

The sports car has a mass of 1.5 Mg and a center of mass at G. Determine the shortest time it takes for it to reach a speed of 80 km/h, starting from rest, if the engine only drives the rear wheels, whereas the front wheels are free rolling. The coefficient of friction between the wheels and road is = 0.2. Neglect the mass of the wheels for the calculation.

Gear A has a weight of 1.5 lb, a radius of 0.2 ft, and a radius of gyration of k_o = 0.13ft. The coefficient of friction between the gear rack B and the horizontal surface is = 0.3. If the rack has a weight of 0.8 lb and is initially sliding to the left with a velocity of (v_B)₂ = 8 ft/s to the left. Neglect friction between the rack and the gear and assume that the gear exerts only a horizontal force on the rack.