最美情侣中文字幕电影,在线麻豆精品传媒,在线网站高清黄,久久黄色视频

歡迎光臨散文網(wǎng) 會員登陸 & 注冊

物理復習

2023-06-05 13:29 作者:鉛灰線  | 我要投稿

Chapter1 kinematics

1.displacement:Δx=x-x0

2.speed-velocity

1speed=d/t

2v=dx/dt

3.acceleration

1a=dv/dt

2constant acceleration

x=x0+1/2v+v0t=x0+v0t+1/2 at*2

v=v0+at

v*2-v0*2=2aΔx

?

Chapter2 dynamics

1ΣF=ma,ΣF means net external force

N=kg m s*-2

2 gravitational force

F=GMm r*-2),GM=gR*2

3 overweight weightless

Fn(support force)=mg+ma

1Fn is the reading of the scale, and mg is actually the weight.

2when the a0,Fnmg,overweight,and weightless the opposite

4 static and kinetic frictional force

1fsfsmax=μsFn (actually the maximum of static frictional force is larger than constant kinetic frictional force )

?

Chapter 3 Work and energy

1 W=Fs=|F||S|cosα

2 kinetic energy(動能)

1Ek=1/2 mv*2

(2) the work done by net external force equal to the change of the kinetic energy:

W=Ekf-Ek0

3 gravitational potential energy(重力勢能)

Wg=mg(h0-hf)=-mgΔh

Epg=mgΔh

4 elastic potential energy(彈性勢能)

Eptension=1/2k(Δx*2

5 mechanical energy

(1)Emc=Ek+Ep

(2)Wnc=ΔEk+ΔEp

the force external to the system leads to the change of the mechanical energy, and calculate by the change of kinetic energy and the potential energy. That is to say, we can use the mechanical energy to solve the problem in a system

compare to the constancy in mechanical energy theorem of kinetic energy is to solve the problem in an object. For instance, if you work out the net force on an object and the relative distance, you can calculate the total work and thus know the change of the kinetic energy.

6 Power(功率)

P=W/t

?

Chapter 4 Impulse and momentum

1 impulseJ=(ΣF)Δt

2momentump=mv

3(ΣF)Δt=mvf-v0

1the change of momentum can be calculated by impulse

2if the net external force is zero,the momentum will be constant

4collision

1elastic one:ΔEk=0but momentum remains the same

(2)inelastic one:ΔEk0 ,and stick together while completely inelastic

5center

1Xcm=Σ(i=1nmixi/Σ(i=1,nmi

2Vcm=Σ(i=1nmivi/Σ(i=1,nmi

?

?

?

Chapter 5 uniform circular motion

1translational to rotational

(1) x=x0+v0t+1/2at*2,θ=θ0+ω0t+1/2αt*2;x=rθ

(2)v,ω;v=rω

(3)a=dx/dt,α(角加速度)=dθ/dt

(4)v=v0+at,ω=ω0+αt,v=rω

(5)m,I=mr*2

(6)F=ma, =Fxr,

(7)Ek=1/2mv*2,Ek’=1/2Iw*2

(8)W=Fx=┏θ

(9)dim clockwise as negative direction

2.θ=Δv/v=vΔt/r---Δv/Δt=v*2/r=ac

3.v=2Πr/T=rω

4.acceleration

1ac=v*2/r=rω*2directionto the center

2aT=rα=r dω/dt,direction tangential(切向)

5. =Fxr=Iα

1||=|F||r|sinθ

2positive direction counter clockwise

6.I

(1) one point:I=mr*2

2x pointsI=Σmiri*2

3ring

I=mr*2


4rod

I=1/3mL*2

I=1/12mL*2

5plate roundI=1/2Mr*2

6ballI=2/5mR*2

7I=Ic+md*2

ball on the ground:(1+2/5mR*2

ring(實心):(1+1/2mR*2

?

7.W=┏θ

8.Ek=1/2Iω*2

9.Langular momentum,角動量)=Iω

?

?

Chapter 6 Simple Harmonic Motion,elasticity

ideal springF=-kx

1.x=Acosωt,ω=2Πf=2Π(T*-1

2.v=Aωcosωt, a=Aω*2 cosωt

3.F=kx=max

1-kAcosωt=-mAω*2cosωt

(2) ω=(k/m)*0.5

4.energy: Ep=1/2kx*2

model of pendulum

1.1)Σ┏=Fx=-mgLsinθ=-mgLθ

2)θ=Acos cosωt/L

3)Σ┏=-mgLcosωt

2.1 Σ┏=Iα

2)α=a/L=-ω*2Acosωt/L

3combine together:ω=mgL/I*0.5

two other models

1.F=Y(ΔL/L0A

2.F=S(Δx/L0A


Chapter7 fluid

1.Δp=ρhg,F=ρgV

2.pascals principleF proportional to Area

1F1/F2=S1/S2

2A1h1=A2h2

3.continuity(流量)

Δm=ρV=ρAvΔt

(1)Δm/Δt=ρVA

(2)ΔV/Δt=Q=Av

4.equation of Bernoulli

P1+1/2ρv1*2+ρgy1= P2+1/2ρv2*2+ρgy2

?

Chapter8 Temperature and heat

1.Tc=5/9Tf-32),T=Tc+273.15

2.liner thermal expansion(熱脹冷縮)

1)ΔL=αL0ΔT

2)ΔV=βL0ΔT

3.Q

(1)Q=cmΔT

2Q=mLit means that if watersolid,0 turns into liquid0how much heat it needs

4.three ways of heat transference

1convection(對流)Q=kAΔTt/L

2conduction(熱傳遞)Q=cmΔT=mL

3radiation(輻射)Q= ξeAtT*4,其中ξ=5.67x10*-8J/sm*2K*4

?

Chapter9 waves and sound

1 conception

(1)A, λ,T,f

2f=1/T,v=λ/T=λf

2 speed of soundv=(γkT/m*0.5

3 sound intensityI

(1)I=P/A

(2)in a sphereA=4Πr*2

3)①Io=10*-12 W/m*2

I=1 W/m*2

4dB:β=10lnI/Io),Io=10*-12 W/m*2

4 doppler effect

fo=fsv±vo/v-+vs

1upperif observer moves to source,+

2lower if source moves to observer,-

?


物理復習的評論 (共 條)

分享到微博請遵守國家法律
修水县| 邛崃市| 南皮县| 吉林省| 长阳| 绩溪县| 东乌| 都江堰市| 封开县| 锡林郭勒盟| 庆城县| 乌兰浩特市| 台南市| 凤台县| 湟中县| 南和县| 江华| 洪湖市| 墨竹工卡县| 阜新市| 筠连县| 嘉义市| 连云港市| 泗水县| 永定县| 庄河市| 石嘴山市| 福建省| 五峰| 吉首市| 南木林县| 乡宁县| 公安县| 尼玛县| 云浮市| 佛山市| 乌兰浩特市| 正阳县| 宁晋县| 会泽县| 怀远县|