1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
lisov135 [29]
2 years ago
12

Un trineo de 20 kg descansa en la cima de una pendiente de 80 m de longitud y 30° de inclinación. Si µ = 0.2, ¿cuál es la veloci

dad al pie del plano inclinado?
Physics
1 answer:
Mariulka [41]2 years ago
6 0

Answer:

v= 26.70 m/seg

Explanation:  Ver anexo ( diagrama de cuerpo libre)

De acuerdo a la segunda ley de Newton

∑ F  =  m*a

∑ Fx  =  m* a(x)             ∑ Fy  =  m* a(y)

También sabemos que el coeficiente de roce dinámico es:

  μ  = 0.2 = F(r)/N            siendo N la fuerza normal.

Si descomponemos la fuerza P = mg  =  20Kg* 9.8m/seg²

P =  196 [N]    en sus componentes sobre los ejes x y y tenemos

Py  =  P* cos30  =  196* √3/2  =  98*√3

Px  = P* sen30   =  196*1/2  =  98

La sumatoria sobre el eje y es :

∑ F(y)  =  m*a         Py  - N  = 0          98*√3  = N       ( no hay movimiento en la dirección y)

∑ F(x)  = m*a    P(x)  -  Fr  =  m*a

Fr  =   μ *N  =  0.2* 98*√3

Fr  =  19.6*√3  [N]

98 -  19.6*√3  =  m*a

98  -  33.52  = m*a

a =  (98  -  33.52 ) / 20

a = 3.22 m/seg²

Para calcular la velocidad del trineo al pié del plano, sabemos que al pié del plano el trineo ha recorrido 80 m, y que de cinemática

v²  =  v₀²  +  2*a*d             ( se pueden chequear unidades para ver la consistencia de la ecuación  v  y  v₀    vienen dados en m/seg  entonces  v²  y  v₀²  vienen en m²/seg²,  el producto de a (m/seg²) por la distancia d (m) resulta en m²/seg²  entonces es consistente la relación

v²   =  0   +  2*3.22*80       ( la velocidad inicial es cero)

v²  = 515.2  m²/seg²

v  =  √515.2  m/seg

v= 26.70 m/seg

You might be interested in
The x-axis of a trajectory represents its _____.
sineoko [7]
The x-acis of a trajectory represents its C
3 0
3 years ago
Read 2 more answers
A car starts from rest and accelerates at a constant rate after the car has gone 50 m it has a speed of 21 m/s what is the accel
Leya [2.2K]

Answer:

4.41 m/s^2

Explanation:

(v_f)^2 - (v_i)^2 = 2a * change in distance

(21)^2 - (0)^2 = 2a * 50

a = (21^2)/(2*50)

a = 4.41 m/s^2

3 0
3 years ago
What is 6.9 × 107 written in standard form?
n200080 [17]
Answer: 6.9x 107 in standard form is 69,000,000

7 0
2 years ago
Read 2 more answers
A wave seen at the ocean’s shore is which kind of wave?
Lostsunrise [7]
B. Transverse Wave this is the correct answer
3 0
3 years ago
Read 2 more answers
What is the relationship between the atoms of elements,its isotopes and its ions
klasskru [66]
An element refers to a collection of atoms having the same number of protons and electrons (an atomic number). In each element there is a different atomic number due to a different amount of protons in the nucleus.

An isotope is a variation of an element that contains a different number of neutrons, therefore adding weight to the atom.

An ion is a charged atom, and its charge shows how many electrons it needs to gain or lose in order to become stable.
6 0
3 years ago
Other questions:
  • Imagine a landing craft approaching the surface of Callisto, one of Jupiter's moons. If the engine provides an upward force (thr
    14·1 answer
  • Why the substance on the periodic talbe classified together​
    13·2 answers
  • The rate at which current flows is measured in .
    12·2 answers
  • A rigid rod of length L rotates about an axis perpendicular to the rod, with one end of the rod fixed to the axis. Which of the
    6·1 answer
  • A ball on the end of a string is whirled around in a horizontal circle of radius 0.478 m. The plane of the circle is 1.02 m abov
    10·1 answer
  • A 100 m cable is stretched from the ground to the top of a pole. If the angle of the cable with the ground is 10 degrees, how hi
    7·1 answer
  • What are the three subatomic particles of an atom?
    6·2 answers
  • Can someone solve this problem and explain to me how you got it​
    8·1 answer
  • Four seconds after being launched, what is the height of a ball that starts from a height of 12 m with an initial upward velocit
    13·1 answer
  • What Is the west component of 85 m 25 north of west
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!