What is the formula for calculating the force of friction?
A m × g
B μ × N
C N / μ
D F × d
The force of friction is calculated by multiplying the coefficient of friction (μ) by the normal force (N). This force resists the relative motion of two objects in contact.
Which type of force is not a contact force?
A Gravitational force
B Tension force
C Frictional force
D Normal force
Gravitational force is a non-contact force that acts over a distance between two masses, unlike friction, tension, and normal forces, which require physical contact.
What does the term “kinematics” refer to?
A Study of energy
B Study of forces
C Study of material properties
D Study of motion without considering forces
Kinematics focuses on describing the motion of objects, including velocity, acceleration, and displacement, without taking into account the forces causing the motion.
Which of the following is an example of a simple machine?
A Engine
B Motor
C Pulley
D Gear
A pulley is a simple machine that changes the direction of applied force. It can also provide mechanical advantage, depending on the number of pulleys in the system.
What is the purpose of a beam in structural engineering?
A To support loads and resist bending
B To resist torsion
C To resist compression
D To resist shear forces
Beams are structural elements designed to support loads and resist bending due to applied forces, ensuring the stability and strength of a structure.
Which of the following defines momentum?
A Mass × Acceleration
B Mass × Distance
C Mass × Velocity
D Force × Time
Momentum is the product of an object’s mass and its velocity. It is a vector quantity that represents the motion of a body.
What is the principle of virtual work used for?
A To calculate forces
B To analyze equilibrium of structures
C To measure displacement
D To analyze rotational motion
The principle of virtual work is used to determine the equilibrium conditions of structures by considering virtual displacements and ensuring that work done by external forces is zero.
What is the center of gravity of an object?
A The geometric center
B The center of its material
C The center of volume
D The point where weight is balanced
The center of gravity is the point where the total weight of an object acts. It is the balance point under the influence of gravity.
What type of stress occurs when a material is stretched?
A Tensile stress
B Shear stress
C Bending stress
D Compressive stress
Tensile stress occurs when a material is stretched, causing it to elongate. It is the force per unit area that pulls the material apart.
What is the formula for calculating mechanical advantage of a lever?
A Force × Distance
B Effort arm / Load arm
C Load arm / Effort arm
D Output force / Input force
The mechanical advantage of a lever is calculated by dividing the length of the effort arm by the length of the load arm. It shows how much the lever amplifies the force applied.
What does the term “statics” refer to?
A Study of energy
B Study of motion
C Study of forces and equilibrium
D Study of material deformation
Statics deals with analyzing forces and moments acting on structures at rest or in equilibrium. It ensures that structures are stable and not subject to undesirable motion.
Which of the following best defines a couple in mechanics?
A A pair of equal and opposite forces acting at different points
B A pair of equal and opposite forces with a common point of action
C Forces that act in the same direction
D A single force acting on an object
A couple consists of two equal and opposite forces applied at different points, creating a moment that causes rotational motion without translation.
What is the formula for calculating the strain in a material?
A Stress × Area
B Force × Distance
C Force / Area
D Change in length / Original length
Strain is the measure of deformation in a material and is calculated by dividing the change in length by the original length. It is a dimensionless quantity.
What does the term “work” refer to in mechanics?
A Energy stored in an object
B The velocity of an object
C The force multiplied by the displacement in the direction of the force
D The force applied to an object
Work is the energy transferred when a force acts over a distance. It is calculated as W = F × d, where F is the force and d is the displacement in the direction of the force.
What is the formula for calculating the critical buckling load of a column?
A Pcr = π²EI / L²
B Pcr = π²EI / (KL)²
C Pcr = π² / E
D Pcr = EI / L
The critical buckling load (Pcr) for a column is calculated using Euler’s formula: Pcr = π²EI / (KL)², where E is the modulus of elasticity, I is the moment of inertia, K is the effective length factor, and L is the length of the column.