2-70 할리데이 10판 솔루션 일반물리학 {Particle 1=AParticle 2=B\begin{cases} \text{Particle 1}=A\\ \text{Particle 2}=B\\ \end{cases} {Particle 1=AParticle 2=B {xA=6.00t2+3.00t+2.00aB=−8.00tvB(0)=15[m/s]\begin{cases} x_A=6 .00t^2 + 3 .00t + 2.00\\ a_B=-8.00t\\ v_B(0)=15\ut{m/s}\\ \end{cases} ⎩⎨⎧xA=6.00t2+3.00t+2.00aB=−8.00tvB(0)=15[m/s] vA(k)=vB(k)=? v_A(k)=v_B(k) =?vA(k)=vB(k)=? vA(t)=x˙A= dxA dt= d dt(6.00t2+3.00t+2.00)=12t+3 \begin{aligned} v_A(t)&=\dot{x}_A=\dxt{x_A}\\ &=\dt(6 .00t^2 + 3 .00t + 2.00)\\ &=12t+3 \end{aligned} vA(t)=x˙A=dtdxA=dtd(6.00t2+3.00t+2.00)=12t+3 $$ \begin{aligned} v_B(t)&=\int_0^ta\dd t\\ &=\int(-8.00t)\dd t\\ &=-4t^2+C\\ &=-4t^2+15 \ (\becau.. 10판/2. 직선운동 2019.08.05
2-69 할리데이 10판 솔루션 일반물리학 x(16)−x(0)=? x(16)-x(0) =?x(16)−x(0)=? Ans=∫016v dt=∫02v dt+∫210v dt+∫1012v dt+∫1216v dt=12⋅2⋅8+8⋅8+12⋅2⋅(8+4)+4⋅4=100[m] \begin{aligned} \Ans &= \int_0^{16}v\dd t\\ &= \int_0^2v\dd t+\int_2^{10}v\dd t+\int_{10}^{12}v\dd t+\int_{12}^{16}v\dd t\\ &=\frac{1}{2} \cdot 2 \cdot 8 + 8 \cdot 8+\frac{1}{2} \cdot 2 \cdot (8+4)+4\cdot4\\ &= 100\ut{m} \end{aligned} Ans=∫016vdt=∫02vdt+∫210vdt+∫1012vdt+∫1216vdt=21⋅2⋅8+8⋅8+21⋅2⋅(8+4)+4⋅4=100[m] 10판/2. 직선운동 2019.08.05
2-68 할리데이 10판 솔루션 일반물리학 v(40)=? v(40) =?v(40)=? Ans=∫0401000a dt=∫101000201000a dt+∫201000301000a dt+∫301000401000a dt=12⋅0.01⋅100+12⋅0.01⋅(100+400)+12⋅0.01⋅400=5[m/s] \begin{aligned} \Ans &= \int_0^{\frac{40}{1000}}a\dd t\\ &= \int_{\frac{10}{1000}}^{\frac{20}{1000}}a\dd t+\int_{\frac{20}{1000}}^{\frac{30}{1000}}a\dd t+\int_{\frac{30}{1000}}^{\frac{40}{1000}}a\dd t\\ &=\frac{1}{2}\cdot0.01\cdot100+\frac{1}{2}\cdot0.01\cdot(100+400)+\frac{1}{2}\cdot0.01\cdot400\\ &=5\ut{m/s} \end{aligned} Ans=∫0100040adt=∫100010100020adt+∫100020100030adt+∫100030100040adt=21⋅0.01⋅100+21⋅0.01⋅(100+400)+21⋅0.01⋅400=5[m/s] 10판/2. 직선운동 2019.08.05
2-67 할리데이 10판 솔루션 일반물리학 {A=No HelmatB=Helmat\begin{cases} A = \text{No Helmat}\\ B = \text{Helmat}\\ \end{cases} {A=No HelmatB=Helmat ∣maxvA−maxvB∣=? \abs{\max v_A -\max v_B} =?∣maxvA−maxvB∣=? $$ \begin{aligned} \Ans =&\max v_A -\max v_B \ (\because v_A > v_B)\\ =&v_A(0.007) - v_B(0.007) \ (\because a_A,a_B>0)\\ =&\int_0^{0.007}a_A\dd t-\int_0^{0.007}a_B\dd t\\ =&\(\int_0^{0.002}a_A\dd t+\int_{0.002}^{0.004}a_A\dd t+\int_{0.004}^{0.006}a_A\dd t+\int_{0.006}^{0.007}a_A\dd t\)\\ &-.. 10판/2. 직선운동 2019.08.05
2-66 할리데이 10판 솔루션 일반물리학 (풀이자주:문제에 있는 vs=8.0[m]v_s=8.0\ut{m}vs=8.0[m]는 오타로 추정됩니다. 아마 (m/s)를 의도한 것으로 보입니다.) {v(0)=0v(10)=2.0[m/s]v(50)=4.0[m/s]\begin{cases} v(0)=0\\ v(10)=2.0\ut{m/s}\\ v(50)=4.0\ut{m/s}\\ \end{cases} ⎩⎨⎧v(0)=0v(10)=2.0[m/s]v(50)=4.0[m/s] (a)Δx0→50=?\Delta x_{0\to50}=?Δx0→50=? $$ \begin{aligned} x(50)-x(0)&=\int^{\frac{50}{1000}}_{0}v\dd t\\ &=\int_{0}^{\frac{10}{1000}}v\dd t+\int_{\frac{10}{1000}}^{\frac{50}{1000}}v\dd t\\ &=\frac{1}{2}\cdot \frac{10}{1000} \cdot 2 + \frac{1}{2} \cdot \frac{40}{1000.. 10판/2. 직선운동 2019.08.05
2-65 할리데이 10판 솔루션 일반물리학 {A=HeadB=Body\begin{cases} A=\text{Head}\\ B=\text{Body}\\ \end{cases} {A=HeadB=Body (a)vA160=?v_{A160}=?vA160=? $$\begin{cases} v_0=0\\ a_A = \text{Linear} & \\ a_A(t) = 0 &(t 10판/2. 직선운동 2019.08.05
2-64 할리데이 10판 솔루션 일반물리학 {x1=0t1=3.0[s]v0=−10[m/s]a=−g=−9.80665[m/s2]\begin{cases} x_1=0\\ t_1=3.0\ut{s}\\ v_0=-10\ut{m/s}\\ a=-g = -9.80665\ut{m/s^2}\\ \end{cases} ⎩⎨⎧x1=0t1=3.0[s]v0=−10[m/s]a=−g=−9.80665[m/s2] x0=? x_0=?x0=? Δx=v0t+12at2,x1−x0=(−10)(3.0)+12(−g)(3.0)2x0=30+92g=30+92(9.80665)=296519740000[m]=74.1299[m]≈74[m] \begin{aligned} \Delta x &= v_0t+\frac{1}{2}at^2,\\ x_1-x_0&= (-10)(3.0)+\frac{1}{2}(-g)(3.0)^2\\ x_0&= 30+\frac{9}{2} g\\ &= 30+\frac{9}{2}(9.80665)\\ &=\frac{2965197}{40000}\ut{m}\\ &=74.1299\ut{m}\\ &\approx 74\ut{m}\\ \end{aligned} Δxx1−x0x0=v0t+21at2,=(−10)(3.0)+21(−g)(3.0)2=30+29g=30+29(9.80665)=400002965197[m]=74.1299[m]≈74[m] 10판/2. 직선운동 2019.08.03
2-63 할리데이 10판 솔루션 일반물리학 {t1=FlowerPot is Bottom of Windowt2=FlowerPot is Top of Windowt3=FlowerPot is Top Point \begin{cases} t_1 = \text{FlowerPot is Bottom of Window}\\ t_2 = \text{FlowerPot is Top of Window}\\ t_3 = \text{FlowerPot is Top Point}\\ \end{cases} ⎩⎨⎧t1=FlowerPot is Bottom of Windowt2=FlowerPot is Top of Windowt3=FlowerPot is Top Point {x0=0x1→2=2.00[m]t1→2=0.50[s]v3=0a=−g=−9.80665[m/s2]\begin{cases} x_0=0\\ x_{1\to2}=2.00\ut{m}\\ t_{1\to2}=0.50\ut{s}\\ v_3=0\\ a=-g = -9.80665\ut{m/s^2}\\ \end{cases} ⎩⎨⎧x0=0x1→2=2.00[m]t1→2=0.50[s]v3=0a=−g=−9.80665[m/s2] x2→3=? x_{2\to3}=?x2→3=? Δx=vt−12at2, \Delta x = vt-\frac{1}{2}at^2,Δx=vt−21at2, Δx1→2=v2t1→2−12(−g)t1→22 \Delta x_{1\to2} = v_2t_{1\to2}-\frac{1}{2}(-g)t_{1\to2}^2Δx1→2=v2t1→2−21(−g)t1→22 $$ .. 10판/2. 직선운동 2019.08.03
2-62 할리데이 10판 솔루션 일반물리학 {t1=Man is 15cm From Bottom 1st Timet2=Man is Under 15cm From Top 1st Timet3=Man is Top Pointt4=Man is Under 15cm From Top 2st Timet5=Man is 15cm From Bottom 2nd Timet6=Man is Landing \begin{cases} t_1 = \text{Man is 15cm From Bottom 1st Time}\\ t_2 = \text{Man is Under 15cm From Top 1st Time}\\ t_3 = \text{Man is Top Point}\\ t_4 = \text{Man is Under 15cm From Top 2st Time}\\ t_5 = \text{Man is 15cm From Bottom 2nd Time}\\ t_6 = \text{Man is Landing}\\ \end{cases} ⎩⎨⎧t1=Man is 15cm From Bottom 1st Timet2=Man is Under 15cm From Top 1st Timet3=Man is Top Pointt4=Man is Under 15cm From Top 2st Timet5=Man is 15cm From Bottom 2nd Timet6=Man is Landing $$\begin{cases} x_0=x_6=0\\ x_3=0.780\ut{m}\\ v_3=0\\ x_1=x_5=0.150\ut{m}\\ x_2=x_4=x_3-0.150\ut{m}\\ a=-g.. 10판/2. 직선운동 2019.08.02
2-61 할리데이 10판 솔루션 일반물리학 {t0=Ball is Top of Buildingt1=DownBall is Top of Windowt2=DownBall is Bottom of Windowt3=Ball is Contact Roadt4=UpBall is Bottom of Windowt5=UpBall is Top of Window \begin{cases} t_0 = \text{Ball is Top of Building}\\ t_1 = \text{DownBall is Top of Window}\\ t_2 = \text{DownBall is Bottom of Window}\\ t_3 = \text{Ball is Contact Road}\\ t_4 = \text{UpBall is Bottom of Window}\\ t_5 = \text{UpBall is Top of Window}\\ \end{cases} ⎩⎨⎧t0=Ball is Top of Buildingt1=DownBall is Top of Windowt2=DownBall is Bottom of Windowt3=Ball is Contact Roadt4=UpBall is Bottom of Windowt5=UpBall is Top of Window $$\begin{cases} \Delta t_{1\to2}=0.125\ut{s}\\ \Delta t_{4\to5}=0.125\ut{s}\\ \Delta t_{2\to4}=2.00\ut{s}\\ x_0=h\\ x_{1\to2}.. 10판/2. 직선운동 2019.08.02