Angular and Linear Acceleration in Rigid Bodies

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What type of analysis involves the evaluation of input forces, joint forces, and motion of members?

Kinetic force analysis

Static force analysis

Inertial force analysis

Dynamic force analysis (correct)

What is the relationship between inertia force and accelerating force?

Inertia force is opposite in direction to the accelerating force

Inertia force is less than the accelerating force

Inertia force is equal in magnitude to the accelerating force (correct)

Inertia force is greater than the accelerating force

What is the formula for inertia force where 'm' is the mass of the body and 'a' is the linear acceleration?

$Inertia force = m \times a$

$Inertia force = -m \times a$

$Inertia force = -m/a$ (correct)

$Inertia force = m/a$

What does the inertia torque do when applied to a rigid body?

Brings the body in an equilibrium position Signup and view all the answers

How can a system of forces acting on a rigid body be reduced for analysis?

To a single resultant force Signup and view all the answers

What do two equal and opposite forces acting through the center of gravity of a body create?

A couple and a parallel force Signup and view all the answers

What is the formula for moment of inertia of a body about an axis passing through its centre of gravity and perpendicular to the point in which a couple acts?

I = m * k^2 Signup and view all the answers

In a rigid body, what does the equal and opposite force -m.a represent according to D-Alembert's Principle?

Inertia force Signup and view all the answers

What are V-threads mainly used for?

Preventing the nut from slackening Signup and view all the answers

What is the distance between the top and bottom surfaces of a screw thread known as?

Depth of thread Signup and view all the answers

What is the main advantage of V-threads over square threads?

Increased frictional resistance Signup and view all the answers

What is the curve traced by a particle while moving along a screw thread called?

Helix Signup and view all the answers

If the lead of a screw is equal to its pitch, what type of screw is it?

Single-threaded screw Signup and view all the answers

'FI' in D-Alembert's Principle stands for:

Fictitious Inertia Signup and view all the answers

'H' in the formula 'F × h' represents:

'H' as perpendicular distance between force and center of gravity Signup and view all the answers

What type of force acts at the circumference of the rotating shaft?

Frictional force Signup and view all the answers

In order for rotation to be maintained, what must be present?

A couple rotating the shaft Signup and view all the answers

What is the relationship between the resultant force and weight (W) for uniform motion?

R = W Signup and view all the answers

What is the formula for the frictional torque (T) when the shaft rotates with angular velocity rad/s?

$T = µ.W.r$ Signup and view all the answers

What is used to take the axial thrust of rotating shafts?

Pivots and collar bearings Signup and view all the answers

What type of bearing surface is most commonly used for collars in modern practice?

Flat bearing surface Signup and view all the answers

What is assumed in the study of friction of bearings regarding pressure distribution?

Pressure is uniformly distributed Signup and view all the answers

What does a flat pivot bearing (foot step bearing) support?

$W = \text{Load transmitted over the bearing surface}$ Signup and view all the answers

What does the intensity of wear depend on in a bearing?

$v = \text{Velocity of rubbing surfaces}$ Signup and view all the answers

What is responsible for reducing pressure intensity along rubbing surfaces in bearings?

Multiple pivots at different radii Signup and view all the answers

In collar bearings, what is another common term used to refer to them?

Thrust bearings Signup and view all the answers

What is the formula to calculate the total frictional torque on a collar bearing?

$\int_{r2}^{r1} \left(\dfrac{CdA}{r}\right)$ Signup and view all the answers

What is the power absorbed in friction at the thrust block for uniform pressure in Example 1?

26.4 kW Signup and view all the answers

If a shaft has an external collar diameter of 400 mm and shaft diameter of 250 mm, what is the internal collar diameter (r2) in mm?

125 Signup and view all the answers

What is the coefficient of friction used in Example 2 for estimating the power absorbed?

0.35 Signup and view all the answers

In Example 2, what is the calculated number of collars required for the given scenario?

6 Signup and view all the answers

What is the relationship between the rate of wear and the intensity of pressure and velocity of rubbing surfaces?

Directly proportional Signup and view all the answers

What does the intensity of normal pressure vary inversely with in the case of uniform wear?

Distance from the central axis Signup and view all the answers

What is the power lost in friction estimated based on in the given example?

Uniform pressure distribution and coefficient of friction Signup and view all the answers

What does a conical pivot bearing support according to the provided text?

A shaft carrying a load Signup and view all the answers

What is the semi angle of the cone in a conical pivot bearing supporting a load?

60 degrees Signup and view all the answers

In a trapezoidal or truncated conical pivot bearing, what is considered when calculating total torque on the bearing?

External and internal radius Signup and view all the answers

What is the total load transmitted to the ring in case of uniform wear with an external and internal radius in a frustum of a cone?

$2ig(rac{C}{r}ig)dr$ Signup and view all the answers

What does the power absorbed in friction depend on in collar bearings?

Axial thrust of rotating shafts Signup and view all the answers

What is used to take the axial thrust of rotating shafts according to the text?

Flat Collar Bearing Signup and view all the answers

In uniform wear problems, what is assumed to be uniform?

Pressure distribution Signup and view all the answers

What is placed on the head of the square threaded rod in a screw jack?

Load to be raised or lowered Signup and view all the answers

What is the coefficient of friction, denoted by µ, between the screw and nut?

tan ø Signup and view all the answers

In a V-thread (acme or trapezoidal threads), why is the normal reaction between the screw and nut increased?

Axial load W is increased Signup and view all the answers

What does the coefficient of friction µ1 represent in a journal bearing?

Coefficient of friction for the collar Signup and view all the answers

What is the total torque required to overcome friction when an effort P1 is applied at the end of a lever?

$W tan(a + f)$ Signup and view all the answers

Which force acts downwards in a screw jack when lifting a load?

$µ.RN$ Signup and view all the answers

What represents the reaction RN in an inclined plane similar to that of a screw jack?

$W cosa$ Signup and view all the answers

What is meant by point A in relation to a journal bearing?

[point A] is known as seat or point of pressure Signup and view all the answers

What kind of pair does a journal bearing form with its fixed outer element?

[Journal bearing forms] a turning pair Signup and view all the answers

What is required to overcome the friction at the collar in a screw jack?

Coefficient of friction µ1 for the collar Signup and view all the answers