Write My Paper Button

What do you understand by static equilibrium of a rigid body? (2 marks) (b) A force ๐… of magnitude 50 N is exerted on the automobile parking-brake lever at the position ๐‘ฅ = 250 mm as shown in the figure below. Determine the moment of this force about point ๐‘‚. (6 marks) (c) To accommodate the rise and fall of the tide, a walkway from a pier to a float is supported by two rollers as shown in figure 1 below. Figure 1 The mass center of the 300-kg walkway is at ๐บ.

UNIVERSITY EXAMINATIONS 2024/2025
Coursework Assignment 1
October 21, 2024
Instructions
1. Diploma students should answer questions 1, 2, 3 and 4.
2. All other students should answer questions 2, 4, 5 and 6.
Question 1
(a) What do you understand by static equilibrium of a rigid body? (2 marks)
(b) A force ๐… of magnitude 50 N is exerted on the automobile parking-brake lever at the position ๐‘ฅ = 250 mm as shown in the figure below. Determine the moment of this force about point ๐‘‚. (6 marks)

(c) To accommodate the rise and fall of the tide, a walkway from a pier to a float is supported by two rollers as shown in figure 1 below.

Figure 1
The mass center of the 300-kg walkway is at ๐บ.
(i) What is meant by mass center of a body? (2 marks)
(ii) Calculate the tension T in the horizontal cable which is attached to the cleat and the force under the roller at ๐ด. (10 marks)
Question 2
(a) Explain the significance of idealizing a body as a particle
and a rigid body. (4 marks)
(b) The masthead fitting supports the two forces shown in figure 2 below.
(i) Explain clearly the inference of the words underlined. (2 marks)
(ii) Determine the magnitude of ๐“ which will cause no bending of the mast. (14 marks)

Figure 2
Question 3
The pulley and gear are subjected to the loads shown in figure 3 below.

Figure 3

(a) Write each force in vector form. (6 marks)
(b) Find the vector form of the resultant force acting on the system. (2 marks)
(c) Determine the magnitude of the moment caused by the forces about the point ๐‘‚. (12 marks)
Question 4
(a) Explain, with the aid of a simple sketch, what is meant by rectangular components of a force. (2 marks)
(b) A 50-N horizontal force is applied to the handle of the industrial water valve as shown in figure 4 below. The force is perpendicular to the vertical plane containing the line OA of the handle.

Figure 4
(i) Determine the rectangular components of the force.
(6 marks)
(ii) By taking point A on the line of action of the force, find the moment of the force about the origin. (12 marks)

Question 5
(a) Explain, with the aid of a simple sketch, how you can determine the moment of a force about a line using vector formulation. (4 marks)
(b) A 300-N force is applied to the handle of the winch as shown in figure 5 below. The force lies in the plane which is parallel to the ๐‘ฆ-๐‘ง plane and is perpendicular to line ๐ด๐ต of the handle. Determine the moment of this force about the x-axis. (16 marks)

Figure 5
Question 6
(a) State all the necessary and sufficient conditions for equilibrium of a rigid. (6 marks)
(b) A rectangular sign cover of a store shown in figure 6 has a mass of 100kg, with the center of mass in the center of the rectangle. The support against the wall at ๐ถ may be treated as a ball-and-socket joint. At corner ๐ท, support is provided in the ๐‘ฆ-direction only.

Calculate the tensions ๐‘‡1 and ๐‘‡2 in the supporting
wires, the total force supported at C and the lateral
force, ๐‘… supported at corner ๐ท. (14 marks)

Figure 6

WhatsApp Widget
GET YOUR PAPER DONE