kawthar report 2

Weekly Assessment 1 (15%)

Introduction to Mechanical Engineering Design, Innovation & Entrepreneurship

ME 263

Semester: Summer 2020

2019-2020

Page 2 of 2

1. Select any 5 design considerations and explain them with examples. (20 points)

2. Three blocks A, B and a grooved block C have dimensions:

A = 72.5 ± 0.5 mm B = 30 ± 0.3 mm C = 38 ± 0.4 mm

a) Determine the mean clearance (𝑤 ) and its tolerance (tw). (20 points)

b) Determine the mean (nominal) size of (𝐵 ) that will assure that clearance W will not

exceed 5 mm. (20 points)

3. A solid circular rod of diameter d and 500 mm length undergoes a bending moment under the

F = 400 N force inducting a stress 𝜎 = 16 𝑀

𝜋𝑑3 .

a) Using a material strength of 170 MPa and a

design factor of 2.5, determine the minimum

diameter of the rod. (20 points)

b) Using the table below, select a preferred

fractional diameter (5 points) and determine the

resulting rod’s factor of safety. (15 points)