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Hi my name is jana. I am a pupil from the Gi_{Subscript textselagymnasium in Munich and I am in a physikclass leaded by Mr. Osswald. cheers
and I like to move, it move it!}

2.9
x(t) = 0,5 a * t²
t = v/a
x(t) = 0,5*a*(v/a)² = 0,5 * v²/a = v²/2*x(t)
a= 3,6 *10⁵ m/s²
t= v/a = 2,1 * 10^-3s_{Subscript text}

3.19 Geg: m=52 kg µ= 0,06 α=22°C x=25m

a) F_g= m * g = 52kg * 9,81 N/kg= 5,1 * 10²N

  Fh= sinα * Fg = 1,9 * 102 N
  a= = 
      = 3,7 m/s2
  v2 = 2*x*a = (2*3,7 m/s2*25m)1/2 = 13,6 m/s2

b) F_Hr = F_h - F_r

  Fr = µ*Fn
  Fn = cos  * Fg = cos(22) * 5,1*102 =
  = 4,7*102 N
  Fr= 0,06  4,7 * 102= 28N
  Fhr= 1,9* 102N - 28N = 1,6 * 102
  a=  = 3,1 m/s2
  v2 = a*2*x = (3,1 m/s2 * 2* 25m)1/2 = 12m/s

c) F_l= F_h + F_r= 1,9*10² N + 28N = 2,2 *10²

  Fl + Fa= F
  Fa = a*m = 2,0 m/s2 * 52kg = 104 N
  F = 104 N + 2,2 * 102 N = 323N

4.6

a)geg m= 2,0t v=50 km/h ges: E_kin= 0.5*m*v²

   = 0.5 * 2000kg * (13,8 m/s)2
   = 192901J = 193kJ

b)H = 200m m=1,0 m³

 Epot= m*g*h = 1962000J =1,9MJ

c)m = 4000m³ = 4000000kg v=1m/s E_kin =0,5*m*v²= 2000000J = 2MJ