INSTRUCTION: This paper consists of SIX (6) essay questions. Answer any FOUR (4) questions only.

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1 INSTRUCTION: This paper consists of SIX (6) essay questions. Answer any FOUR (4) questions only. ARAHAN: Kertas ini mengandungi ENAM (6) soalan esei. Jawab mana-mana EMPAT (4) soalan sahaja. QUESTION 1 SOALAN 1 QUESTION 1 (a) The screw in Figure 1(a) is subjected to two forces, F 1 and F 2. With the aid of a Figure, determine the magnitude and direction of the resultant force. Skru dalam gambarajah 1(a) adalah tertakluk kepada dua daya, F 1 dan F 2. Dengan bantuan gambarajah 1(a), tentukan magnitud dan arah paduan daya. Figure 1(a) Gambarajah 1 (a) [10 Marks] [10 Markah] 2 SULIT

2 (b) Based on Figure 1(b), if θ = 30 and T = 6 kn, express the force in the Cartesian form and determine the magnitude of resultant force acting on the eyebolt and its direction from the positive x-axis. Berdasarkan Gambarajah 1(b), jika θ = 30 dan T = 6 kn, ungkapkan daya dalam bentuk Cartesian dan tentukan magnitud bagi paduan daya yang bertindak ke atas eyebolt dan arah bagi paduan daya daripada paksi-x positif. Figure 1(b) Gambarajah 1(b) [15 Marks] [15 Markah] 3 SULIT

3 C1 QUESTION 2 (a) Describe the conditions and state the formula for the equilibrium of a particle. Jelaskan keadaan dan nyatakan rumus untuk keseimbangan zarah. [5 Marks] [5 Markah] C2 (b) Determine the tension developed in CA and CB wires required for equilibrium of the 10kg cylinder in Figure 2. Take θ = 40. Tentukan tegangan yang terhasil dalam wayar CA dan CB yang diperlukan untuk keseimbangan 10 kg silinder dalam Rajah 2. Ambil θ = 40. Figure 2(b) Gambarajah 2(b) [10 Marks] [10 Markah] 4 SULIT

4 (c) Determine the force in each cable for equilibrium of the 200 kg crate. Cable BC remains horizontal due to the roller at C, and AB has a length of 1.5 m. Set y = 0.75 m. Tentukan daya dalam setiap kabel untuk keseimbangan peti 200 kg. kabel BC kekal dalam keadaan mendatar disebabkan roller di C, dan AB mempunyai panjang 1.5 m. Tetapkan y = 0.75 m. Figure 2(c) Gambarajah 2(c) [10 Marks] [10 Markah] 5 SULIT

5 QUESTION 3 C1 (a) Define and state an example for the following terms: Takrifkan dan nyatakan satu contoh bagi setiap terma berikut: i. Truss Kekuda ii. Frame Kerangka [2.5 Marks] [2.5 Markah] [2.5 Marks] [2.5 Markah] (b) 4m 3m Figure 3(b) Gambarajah 3(b) 4m By refering to figure 3(b), determine the force in members AB and BC if P 1 =200N and P 2 =500N by using joint method. State either the members are in tension or compression Merujuk kepada gambarajah 3(b), tentukan daya dalam anggota AB dan BC jika P 1 = 200N dan P 2 = 500N dengan menggunakan kaedah sambungan sendi. Nyatakan sama ada anggota dalam keadaan tegangan atau mampatan. [20 Marks] [20Markah] 6 SULIT

6 QUESTION 4 (a) The truss used to support a balcony, is subjected to the loading shown in Figure 4(a). Assume each joint as a pin. By using the method of joints determine the force in member CB, CD, DB and DE of truss. State whether the members are in tension or compression. Kekuda digunakan untuk menyokong balkoni yang tertakluk pada beban seperti yang ditunjukkan dalam rajah 4(a). Anggapkan setiap sambungan sebagai pin. Dengan menggunakan kaedah sambungan, tentukan daya pada anggota CB, CD, DB dan DE pada kerangka. Nyatakan samada anggota dalam keadaan tegangan atau mampatan. [12 Marks] [12 Markah] Figure 4(a) Gambarajah 4(a) C2 (b) Describe the difference between Kinematics and kinetics of particles Terangkan perbezaan antara Kinematik dan kinetik zarah 7 SULIT

7 (c) The acceleration of a particle as it moves along a straight line is given by, where is in seconds. If and position when when travels during this time period., determine the particle s velocity and. Also determine the total distance the particle Pecutan suatu zarah bergerak pada satu garis lurus diberikan oleh, dimana t dalam saat. Jika s =1m dan v = 2m/s bila t=0, tentukan halaju zarah dan kedudukan bila t=6s.tentukan juga jumlah jarak oleh zarah sepanjang masa yang dilalui. [9 Marks] [9 Markah] QUESTION 5 C1 (a) Define the following terms : Takrifkan istilah-istilah berikut i. Displacement Sesaran ii. Velocity Halaju iii Acceleration Pecutan [2 Marks] [2 Markah] [2 Marks] [2 Markah] [2 Marks] [2 Markah] 8 SULIT

8 (b) A car has an initial speed of 25 m/s and a constant deceleration of 3m/s 2. Sebuah kereta mempunyai kelajuan awal 25 m /s dan menyahpecut dengan nyahpecutan malar 3m/s 2. i. Calculate the velocity of the car when t = 4 s Kirakan halaju kereta apabila t = 4 s [3 Marks] [3 Markah] ii. Calculate the displacement of the car during the 4 s time interval? Kirakan sesaran kereta dalam selang masa 4 s? iii. How much time is needed to stop the car? Berapa lamakah masa diperlukan untuk menghentikan kereta? (c) A train starts from rest at a station before accelerate with constant acceleration of 1.5 m/s 2 until it achieves velocity of 54 km/h. Then, the train decelerate until it stop in 12 s. Determine : Sebuah kereta api bermula dari keadaan rehat di stesen sebelum memecut dengan pecutan malar iaitu 1.5 m/s 2 sehingga mencapai halaju 54 km/h. Kemudian, kereta api tersebut menyahpecut sehingga ia berhenti dalam masa 12 s. Tentukan: i.. Distance travelled by the train Jarak yang dilalui oleh kereta api tersebut ii. Deceleration of the train Nyahpecutan kereta api tersebut 9 SULIT

9 QUESTION 6 C1 (a) State Newton s Third Law of Motion. Nyatakan Hukum Newton ketiga bagi gerakan [2 Marks] [2 Markah] (b) The 50kg crate rests on a horizontal surface for which the coefficient of kinetic friction is µ k = 0.3. If the crate is subjected to a 400N towing force as shown in Figure 6(b), determine the velocity of the crate in 3s starting from rest. Peti 50kg dalam keadaaan rehat terletak di atas permukaan mendatar yang mana pekali geseran kinetik adalah μk = 0.3. Jika peti itu tertakluk kepada satu daya menunda 400N seperti yang ditunjukkan dalam Gambarajah 6(b), tentukan halaju peti dalam masa 3 saat bermula dari keadaan rehat. Figure 6(b) Gambarajah 6(b) [13 Marks] [13 Markah] 10 SULIT

10 C2 (c) A vehicle of mass kg changes velocity from 2 m/s to 6 m/s. Calculate the change in momentum. Sebuah kenderaan berjisim 5 000kg berubah kelajuan dari 2 m / s kepada 6 m / s. Kirakan perubahan dalam momentum. C2 (d) A 1850 kg luxury sedan stopped at a traffic light is hit from behind by a compact car with a mass of 975 kg. The two cars become entangled as a result of the collision. If the compact car was moving with a velocity of 22.0 m/s to the north before the collision, determine: Sebuah kereta mewah seberat 1850 kg yang berhenti di lampu isyarat dilanggar dari belakang oleh sebuah kereta kompak yang mempunyai jisim 975 kg. Kedua-dua kereta tersebut menjadi terikat akibat perlanggaran. Jika kereta kompak sedang bergerak dengan halaju sebanyak 22.0 m/s ke utara sebelum perlanggaran. Tentukan: i. The velocity of the entangled mass after the collision. Halaju jisim terikat selepas perlanggaran. ii. Direction of the cars after collision Arah pergerakan kereta tersebut selepas pelanggaran [2 Marks] [2 Markah] SOALAN TAMAT 11 SULIT

11 LIST OF FORMULA: JJ205 - ENGINEERING MECHANICS STATICS 1) TRIANGLE LAWS Sin law: A sin a = Cosine law: B sin b = C sin c C = A 2 + B 2 2ABcos c F R = F 2 2 Rx + F Ry θ = tan 1 F Ry F Rx 2) UNIT VECTOR cos 2 α + cos 2 β + cos 2 γ = 1 u A = A A = A x A i + A y A j + A z A k u A = cos α i + cos β j + cos γ k 3) DOT PRODUCT A. B = A x B x + A y B y + A z B z θ = cos 1 [(A. B)/(AB)] DYNAMICS 1) EQUATIONS OF LINEAR MOTION v = u + at (u + v)t s = 2 v 2 = u 2 + 2as s = ut at2 2) EQUATIONS OF ANGULAR MOTION θ = (ω 1 + ω 2 ) 2 ω 2 = ω 1 + α t ω 2 2 = ω αθ θ = ω 1 t + 1 α t2 2 3) KINETIC & POTENTIAL ENERGY T = 1 2 mv2 U 1 2 = V g T 1 + V 2 = T 2 + V 2 4) IMPULSE & MOMENTUM p = m v F ave t I = p f p i = p J = F(t) = m v 12 SULIT

This paper consists of SIX (6) structured questions. Answer any FOUR (4) questions.

INSTRUCTIONS: This paper consists of SIX (6) structured questions. Answer any FOUR (4) questions. ARAHAN: Kertas ini mengandungi ENAM (6) soalan struktur. Jawab mana-mana EMPAT (4) soalan sahaja QUESTION