P-Chem II Course HWK 1 Solutions

# P-Chem II Course HWK 1 Solutions - CHM4411—02[Phys—Chem...

This preview shows pages 1–4. Sign up to view the full content.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: CHM4411—02 [Phys—Chem. 11], Spring 2012 Instructor: H. Mattoussi 5“ a it Your name: —————— “j'j'sri‘“ 4-4;; Exercise 1 (5 points) A classical harmonic oscillator can be described by an ideal spring (with a spring constant k) to which end is attached a mass m. When the mass is moved from its resting position (deﬁned as x=0) to a distance A, then released, it experiences a sustained oscillating motion. 1. Write the fundamental equation of movement. (the friction against the support surface are negligible) ,9 a» ’E% g, “T10 res F57W6€ «a 1" (Zia ft 1 f, (j/‘ﬁﬂx 14. {3;} i / *3 5‘5:er 2. Find the expression for the displacement x(t) as o; A; E? t ' 5 HM" Meg gist “" ‘5‘ ‘ 1 i. are, i g i I lgyg ’1 if A at i . .951: _ 5r a» day) 45:35,; 5’ ' m it éxv’ 5 "4%)? V" t £5 "5?" " ‘ E? ’32:? f a. V ’ l” .l’ \(ﬂ W , a f) if a J a 3. Find the expression for the p(t) g: fie; :— Hi“ ) ,.: raft i363; s 5 43.53“ 4. Show that the total energy, Em = Ekin + Epot, (deﬁned as the sum of the kinetic and potential energies) is constant. / I ‘ 2 C (‘J‘i as? if v fig. :1?" 3st .2: ,1: gf" 70/5171) 3; g, 0 Mac jg 2d .. .~ 5 1 “'°‘ L a“ P i F112, » t a» a; 2"" 52:? - I mi? 5a) éaﬁéﬁl‘i‘tz "r, n ‘a f t M =- m 1 Z 3%? Z ’2 \ ,9 'g Q 1;; r” I” it i“: Z 6 mt an; é: L‘Vﬂﬁ‘it 7 i I g a a: a. 3 5 t ” a?” e ' at? i 3 5 u: “awe g a 2 ix» ,\ / Exercise 2 (5 points) 1) If a force, F , is applied to an object of mass m (initially at rest), What happens to that object? 9* \$53 “ ' ' ‘ i a it? 2) If the force is applied for a given time, 1;, what speed will the object gain (final speed) after the force is removed? W g?) c,“ a». 3:: 21> git; : hgre if) f t” i. "f: M» W” :35?” Wt Va 4) Practical example: an apple falling of a tree: The initial height of the apple is h, its mass m 3 300 mg. Express the force acting on the mass m‘ TATTM/“W vvvv tin“ , /,., .Vmwnwws -” Calculate the speed of the apple when it reaches the ground if the initial height was: 201m (AM; I " ‘ - r 1/ ”‘ (Q) “a! ;: c) 5m Exercice 3 (5 points) The angular momentum of a mass m orbiting around the center 0 is given by: J = rxp (vector product). This angular momentum can be expressed (for small size object) as: I]! = In). 1) What do I and to designate? Z : mmmi if W 5 “Vigeﬁele ’%’£%4aaﬁ,wi, 2) Find a simple expression for l. 323:? V} E "a l g 1% 7‘92“! As done above for the linear motion in exercise 2, to accelerate the mass a torque T is applied to the mass. 3) Write the fundamental equation for this rotation motion: may) , , i 4) What will be the angular momentum of the mass be if the torque T is applied for given time 2' (we need an expression)? Rm»? was“ Exercice 4 (7.2.) (5 points) Explain why Planck’s introduction of quantized energy accounted for the properties of black body radiation. :75? i" [Sac/ray: ; LO gWVMQ/ﬁw amm doll,as¢m; K2! NW7LS‘1’? Cs [5w 9/ mgﬁw- M 01V :’ I: J" 7’" i :1) Q’s/.1“ng and 1/(23): jZ+Vl\$©/) Z 5—94”; My, it’lmz, ﬁceQ/e/J ﬁ‘f M2, A V6494 ﬁle, jam/1A, V(o)::o MO {V}! ha}. QFCoCL. 1 We an Ac ZAML an 6970. ﬁv Z 7 mall/12¢ {ya} .5.) oi}:- as. Qf+€f§ 4/» all” wwm (“)S/Ijh (Anni 4/C M; 47/12 Ivan/‘0) ﬂaw», ,2. :D %[email protected] ~ ~ij+k(tso) L W——-—* 1g 14, .51) “C;- 2" 2‘ ...
View Full Document

{[ snackBarMessage ]}

### Page1 / 4

P-Chem II Course HWK 1 Solutions - CHM4411—02[Phys—Chem...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online