(a) It is easier for a person to push an empty shopping cart than a full one where both carts are originally at rest. From this statement, choose and explain law of Newton suitable for these cases. Assume that the coefficients of static friction are the same for both carts. [Adalah lebih mudah untuk menolak bekas beli belah kosong daripada yang penuh yang mana kedua duanya berada dalam keadaan pegun. Daripada kenyataan ini, pilih dan jelaskan hukum Newton yang sesuai untuk kes ini.] (b) A couple moment, M and forces acting at point O as shown in Figure 1, could be located to point O' to obtain similar effect of translation and rotation with certain approach. Point O and O' having same height from base AB. Using appropriate sketch, explain and justify the above statement. [Momen pasangan M dan daya-daya yang bertindak pada titik o seperti yang ditunjukkan dalam Gambarajah 1, boleh diubah ke titik lain O' bagi menghasilkan kesan pemindahan dan putaran yang sama dengan menggunakan pendekatan yang tertentu. Titik O dan O' mempunyai ketinggian yang sama dari tapak AB. Dengan menggunakan lakaran yang bersesuaian, terangkan dan wajarkan penyataan di atas.]

(a) It is easier for a person to push an empty shopping cart than a full one where both carts are originally at rest. From this statement, choose and explain law of Newton suitable for these cases. Assume that the coefficients of static friction are the same for both carts. [Adalah lebih mudah untuk menolak bekas beli belah kosong daripada yang penuh yang mana kedua duanya berada dalam keadaan pegun. Daripada kenyataan ini, pilih dan jelaskan hukum Newton yang sesuai untuk kes ini.] (b) A couple moment, M and forces acting at point O as shown in Figure 1, could be located to point O' to obtain similar effect of translation and rotation with certain approach. Point O and O' having same height from base AB. Using appropriate sketch, explain and justify the above statement. [Momen pasangan M dan daya-daya yang bertindak pada titik o seperti yang ditunjukkan dalam Gambarajah 1, boleh diubah ke titik lain O' bagi menghasilkan kesan pemindahan dan putaran yang sama dengan menggunakan pendekatan yang tertentu. Titik O dan O' mempunyai ketinggian yang sama dari tapak AB. Dengan menggunakan lakaran yang bersesuaian, terangkan dan wajarkan penyataan di atas.]

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.24P: A uniform plank is supported by a fixed support at A and a drum at B that rotates clockwise. The...

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A uniform plank is supported by a fixed support at A and a drum at B that rotates clockwise. The coefficients of static and kinetic friction for the two points of contact are as shown. Determine whether the plank moves from the position shown if (a) the plank is placed in position before the drum is set in motion; and (b) the plank is first placed on the support at A and then lowered onto the drum, which is already rotating.
The square-threaded screw with a pitch of 10 mm and a mean radius of 18 mm drives a gear that has a mean radius of 75 mm. The static and kinetic coefficients of friction between the gear and the screw are 0.12 and 0.06, respectively. The input torque applied to the screw is C0=10Nm. Assuming constant speed operation, determine the output torque C1 acting on the gear.
A flatbed truck is moving with an acceleration of 6 m/s2. For what value of the coefficient of static friction between the truck bed and a cabinet will the cabinet slip along the bed surface?
Weights of blocks x, y and z are 8 lb, 12 lb and 80 lb respectively. Between all contact surfaces, the coefficient of static friction is 0.40 and that of kinetic friction is 0.30. What vertical force F must be applied to block x, so that block z will start moving upward?
3. A vehicle, mass 1400 kg, passes a bend at a speed of 54 km/hr. The radius of curvature of the road is 60 m. Determine the minimum coefficient of static friction between the car tires and the road, so that the car can pass through corners safely.
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A block with a mass of 100 kg (left-block) is connected to another block of mass M (right-block) by a cable that passes over a fixed drum as shown below. The coefficient of static friction between the left-block and the floor is 0.45, between the right-block and floor is 0.4, and between the cable and the fixed drum is 0.25. Ignore tipping (overturning). Determine the minimum mass of the left-block for which motion does not occur.
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For the system shown, the masses of A and B are 55kg and 135kg, respectively. the coefficient of static friction between block B and surface C is 0.12 and the coefficient of static friction between blocks A and B is 0.10. the coefficient of friction between the rope and the pulley is 0.10. a. What is the tension force in the rope connected to block B if the system is in equillibrium? b. What is the magnitude of the friction force between block B and the horizontal surface C if the system is in equillibrium? c.What is the maximum mass that can be suspended as shown and still maintain equillibrium.