Register to reply

Problems of statics, angular motion and simple harmonic motion

by hjkklm
Tags: angular, harmonic, motion, simple, statics
Share this thread:
Jan6-13, 09:34 PM
P: 12
All Questions are shown on pictures.

My Calculated answers:

A1(a) R= 19.21∠68.7o N
(b) E = 19.21∠-111.34o N or = -19.21∠68.7o N <--- Is't either one answer is correct or not? If not, which answer is correct and why? Thanks.

A2(b) I = 0.5mr2 = 1.125kgm2
A2(a) k=(I/m)1/2 = 0.212m
A2(c) αt=ω, α = 3.14 rad/s2
A2(d) T=Iα = 3.53Nm

I can't gain the answer of A2(a) first. I use the A2(b) answer to help me to gain the A2(a) answer. So, the step of my calculated order is A2(b) -> A2(a) -> A2(c) -> A2(d). Is't correct?

B1(a)(ii) RBY = 1500N

sum of force and moment = 0

RA = 1200N (toward left)
RBX = 1200N (toward right)

B1(b) RBY = 500N
RA = 2012.4N (toward left)
RBX = 1146.4N (toward right)

B2(a) KE = (0.5)(10)(100) = 500J
(b) PE = (10)(9.81)(147.8) = 14503.1J
(c) v2 = {[(500 + 14503.1)x2]/10}0.5 =54.8m/s
(d ) WD = 1.2(230) = 276J , v= {[(15003.1-276)x2]/10}0.5 = 54.3m/s

B3(a) n = 1/0.08 = 12.5Hz
(b) m = (0.08/2π)2(20x103) = 3.24kg
(c) ω = 2π(12.5) = 78.5rad/s, v=78.54x0.01 = 0.785m/s
(d) f = 78.542(0.006) = 37.01m/s2 , T = 2π(0.006/37.01)0.5 = 0.08s
(e) I can't do this part, may you help me, please?

All Questions are shown on pictures.
All above my calculated ans. are correct or not? It there are something wrong, please don't hesitate to correct my answers and give some comment. Thanks a lot.
Attached Thumbnails
A1.JPG   A2.JPG   B1.jpg  
Phys.Org News Partner Science news on
Bees able to spot which flowers offer best rewards before landing
Classic Lewis Carroll character inspires new ecological model
When cooperation counts: Researchers find sperm benefit from grouping together in mice
Jan6-13, 09:36 PM
P: 12
Questions of pictures B2 and B3
Attached Thumbnails
B2.JPG   B3.JPG  

Register to reply

Related Discussions
Angular Simple Harmonic Motion Introductory Physics Homework 1
Angular Simple Harmonic Motion Introductory Physics Homework 3
Simple harmonic motion problems Advanced Physics Homework 3
Simple Harmonic motion problems Introductory Physics Homework 1
Simple Harmonic Motion Problems Introductory Physics Homework 1