Force is measured in Newtons (N) in the SI system. One Newton is defined as the force required to accelerate a mass of one kilogram at a rate of one meter per second squared (1 N = 1 kg·m/s²). Joule is the unit of energy, Pascal is the unit of pressure, and Watt is the unit of power.
Which of the following is a scalar quantity?
A Force
B Velocity
C Mass
D Acceleration
Mass is a scalar quantity because it has only magnitude and no direction. Force, velocity, and acceleration are vector quantities as they have both magnitude and direction.
What is the condition for a body to be in equilibrium?
A Net force is zero
B Net torque is zero
C Both net force and net torque are zero
D Net force is non-zero
For a body to be in equilibrium, both the net force and net torque acting on it must be zero. This ensures that the body is neither translating nor rotating.
What is the formula for calculating work done?
A Force × Distance
B Force × Velocity
C Mass × Acceleration
D Pressure × Volume
Work done is calculated as the product of force and the distance moved in the direction of the force (W = F × d). It is measured in Joules (J).
Which principle states that a body submerged in a fluid experiences an upward buoyant force equal to the weight of the displaced fluid?
A Pascal’s Principle
B Archimedes’ Principle
C Bernoulli’s Principle
D Hooke’s Law
Archimedes’ Principle states that the buoyant force on a submerged object is equal to the weight of the fluid it displaces. This principle is fundamental in hydrostatics and explains why objects float or sink.
What is the unit of stress?
A Newton
B Pascal
C Joule
D Watt
Stress is defined as force per unit area and is measured in Pascals (Pa). One Pascal is equal to one Newton per square meter (1 Pa = 1 N/m²).
Which of the following is an example of a simple machine?
A Lever
B Engine
C Turbine
D Generator
A lever is a simple machine that amplifies force or changes its direction. Other examples of simple machines include pulleys, inclined planes, and screws.
What is the center of gravity?
A The point where mass is concentrated
B The point where weight is balanced
C The geometric center of an object
D The point where external forces act
The center of gravity is the point where the total weight of a body is assumed to act. It is the balance point of an object under the influence of gravity.
What is the formula for momentum?
A Force × Distance
B Mass × Acceleration
C Force × Time
D Mass × Velocity
Momentum (p) is the product of an object’s mass (m) and its velocity (v), given by p = m × v. It is a vector quantity with both magnitude and direction.
Which law states that every action has an equal and opposite reaction?
A Newton’s First Law
B Newton’s Second Law
C Newton’s Third Law
D Hooke’s Law
Newton’s Third Law of Motion states that for every action, there is an equal and opposite reaction. This law explains the interaction between two objects.
What is the formula for mechanical advantage?
A Output Force / Input Force
B Input Force / Output Force
C Output Work / Input Work
D Input Work / Output Work
Mechanical advantage (MA) is the ratio of the output force to the input force in a machine. It measures how much a machine amplifies the input force.
Which of the following is a type of beam support?
A Fixed support
B Hinge support
C Roller support
D All of the above
Beams can be supported in various ways, including fixed supports (restricting all movements), hinge supports (allowing rotation), and roller supports (allowing horizontal movement).
What is the unit of strain?
A Newton
B Pascal
C Dimensionless
D Joule
Strain is the ratio of deformation to the original dimension of a material. Since it is a ratio of two lengths, it is dimensionless.
Which of the following is a measure of a material’s stiffness?
A Shear Modulus
B Bulk Modulus
C Poisson’s Ratio
D Young’s Modulus
Young’s Modulus (E) is a measure of a material’s stiffness and is defined as the ratio of stress to strain in the elastic region. It indicates how much a material will deform under a given load.
What is the principle of virtual work used for?
A Analyzing equilibrium of structures
B Calculating work done by forces
C Determining material properties
D Measuring mechanical advantage
The principle of virtual work is used to analyze the equilibrium of structures by considering virtual displacements. It is a powerful tool in structural mechanics for solving complex problems.