Power is the rate at which work is done. It is calculated as P = W/t, where W is work and t is time. The unit of power is Watt (W).
Which of the following is true for a beam fixed at one end?
A It has a roller support
B It allows rotation at the fixed end
C It restricts both rotation and translation
D It is called a simply supported beam
A beam fixed at one end (cantilever) restricts both rotation and translation at the fixed end. It is commonly used in structures like balconies and bridges.
What is the formula for calculating the moment of inertia?
A Mass × Distance²
B Force × Distance
C Mass × Velocity
D Force / Area
The moment of inertia (I) is a measure of an object’s resistance to rotational motion. It is calculated as I = m × r², where m is mass and r is the distance from the axis of rotation.
Which of the following is true for a truss structure?
A It is made of curved members
B It carries only axial loads
C It cannot carry tension
D It is used only for vertical loads
A truss structure consists of straight members connected at joints, and it carries only axial loads (tension or compression). It is designed to be lightweight and efficient.
What is the formula for calculating the coefficient of friction?
A Mass × Acceleration
B Force × Distance
C Frictional force / Normal force
D Force / Volume
The coefficient of friction (μ) is the ratio of the frictional force to the normal force. It is a dimensionless quantity that depends on the nature of the surfaces in contact.
Which of the following is true for a free-body diagram?
A It includes internal forces
B It is used only for beams
C It shows only external forces
D It ignores equilibrium
A free-body diagram (FBD) is a graphical representation of all external forces acting on a body. It is used to analyze forces and moments in equilibrium problems.
What is the formula for calculating the center of mass?
A Sum of forces / Total mass
B Sum of moments / Total mass
C Sum of distances / Total volume
D Sum of areas / Total length
The center of mass (COM) is calculated as the sum of the moments of individual masses divided by the total mass. It is the point where the mass is balanced.
Which of the following is true for a rigid body?
A It has no deformation under load
B It deforms under load
C It cannot rotate
D It is only used in fluid mechanics
A rigid body is an idealized object that does not deform under load. It is used in mechanics to simplify the analysis of motion and equilibrium.
What is the formula for calculating the angular momentum?
A Mass × Acceleration
B Force × Distance
C Mass × Velocity × Radius
D Force / Area
Angular momentum (L) is the rotational equivalent of linear momentum. It is calculated as L = m × v × r, where m is mass, v is velocity, and r is the radius of rotation.
Which of the following is true for a simply supported beam?
A It has fixed supports at both ends
B It has a hinge support at one end and a roller at the other
C It cannot carry bending moments
D It is used only for vertical loads
A simply supported beam has a hinge support at one end and a roller support at the other. It allows rotation and horizontal movement at the supports.
What is the formula for calculating the strain energy?
A Force × Distance
B Mass × Acceleration
C Force / Area
D 1/2 × Stress × Strain × Volume
Strain energy is the energy stored in a material due to deformation. It is calculated as U = 1/2 × σ × ε × V, where σ is stress, ε is strain, and V is volume.
Which of the following is true for a pulley system?
A It changes the direction of force
B It increases the input force
C It decreases the input force
D It has no mechanical advantage
A pulley system is used to change the direction of the applied force. It can also provide mechanical advantage depending on the number of pulleys used.
What is the formula for calculating the mechanical advantage of a lever?
A Force × Distance
B Mass × Acceleration
C Input arm / Output arm
D Effort arm / Load arm
The mechanical advantage (MA) of a lever is the ratio of the effort arm to the load arm. It indicates how much the lever amplifies the input force.
Which of the following is true for a centroid?
A It is the geometric center of an area
B It is the balance point of a body
C It is often the same as the center of gravity
D All of the above
The centroid is the geometric center of an area, the balance point of a body, and is often the same as the center of gravity for uniform density objects.
What is the formula for calculating the work-energy principle?
A Work done = Change in kinetic energy
B Work done = Change in potential energy
C Work done = Force × Distance
D Work done = Mass × Acceleration
The work-energy principle states that the work done on an object is equal to the change in its kinetic energy. It is expressed as W = ΔKE.