A 1000kg ar accelerates from rest to 25.0m/s in 4.20

Human skin color varies widely around the world, and children do not always exhibit the exact same coloring as their parents. Ba

Ostrovityanka [42]

I would say Its an example of polygenic inheritance because The determination of a particular characteristic, e.g. height or skin colour, by many genes (polygenes), each having a small effect individually. Characteristics controlled in this way show continuous variation.

3 0

2 years ago

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Determine the direction of the force that will act on the charge in each of the following situations. A negative charge moving t

wlad13 [49]

Answer:

a) DOWN direction, b) directed INTO THE SCREEN, c) F = 0

Explanation:

The direction of the force is

for electric force

F = q E

where we assume a positive test charge, for which the force has the direction of the electric field.

For a magnetic field

in this case the direction of the force is given by the right hand rule.

For a positive test charge, the thumb points in the direction of velocity, the other fingers extended in the direction of the magnetic field, and the palm gives the direction of force for a positive charge.

F = q v x B

Let us apply these considerations to our case.

a) negative charge moving to the left

in a magnetic field points away from the screen

In this case the thumb goes to the left, the fingers extended outwards and the palm points upwards, but since the charge is negative the force has a DOWN direction.

b) negative charge moves to the left

in electric field it points off the screen.

The outside is in the direction of the electric field and since the charge is negative, the force is directed INTO THE SCREEN

c) positive charge moves down

in magnetic field points up

in this case the velocity and the field have the same direction so the vector product of them is zero

F = q v B sin 0

F = 0

6 0

3 years ago

If we drop two iron balls, one ball is bigger than another one, from

loris [4]

Answer:

The bigger one. Ignoring air resistance, they will fall at the same speed, but the bigger one will hit first because it sticks out lower.

Explanation:

7 0

2 years ago

A hockey puck is at rest on a flat surface. Then one end of the surface is lifted gradually, forming an inclined plane of increa

Jlenok [28]

The coefficient of static friction between the puck and the surface.

In fact, that coefficient describes exactly how "hard" it is to cause the puck to start moving, if it starts from an idle condition.

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2 years ago

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Una cuerda de 20 pies se estira entre dos arboles. Un peso W cuelga del centro de la cuerda hace que el punto medio de la misma

Galina-37 [17]

Answer:

La magnitud de la masa del peso es 78.447 libras-masa.

Explanation:

La tensión es una fuerza de reacción de la cuerda causada por la acción de una fuerza externa. En este caso, esa fuerza externa es el peso que cuelga en el centro de la cuerda. Abajo hemos adjuntado una representación simplificada del enunciado.

Por las leyes de Newton, tenemos la siguiente ecuación de equilibrio conformada por tres fuerzas:

$\vec T_{1} + \vec T_{2} + \vec W = (0, 0)\, [N]$ (1)

Donde:

$\vec T_{1}$ , $\vec T_{2}$ - Tensiones a cada lado de la cuerda, en newtons.

$\vec W$ - Peso, en newtons.

Si sabemos que $\vec T_{1} = T\cdot (\cos \alpha, \sin \alpha)$ , $\vec T_{2} = T\cdot (-\cos \alpha, \sin \alpha)$ y $\vec W = W\cdot (0, -1)$ , entonces tenemos la siguiente ecuación vectorial:

$T\cdot (\cos \alpha, \sin \alpha) + T\cdot (-\cos\alpha, \sin \alpha) + W\cdot (0, -1) = (0,0)$

$T\cdot (0, 2\cdot \sin \alpha) = W\cdot (0, 1)$

Esto permite reducir la anterior expresión a una fórmula escalar:

$2\cdot T\cdot \sin \alpha = W$

Donde $\alpha$ es el ángulo de inclinación de la cuerda, medido en grados sexagesimales.

El ángulo de inclinación de la cuerda se determina mediante la siguiente fórmula trigonométrica inversa es:

$\alpha = \tan^{-1} \left(\frac{2\,ft}{10\,ft}\right)$

$\alpha \approx 11.310^{\circ}$

Si conocemos que $\alpha \approx 11.310^{\circ}$ y $T = 200\,lbf$ , entonces la magnitud del peso es:

$W = 2\cdot (200\,lb)\cdot \sin 11.310^{\circ}$

$W \approx 78.447\,lbf$

En el Sistema Imperial, las fuerzas son medidas en forma gravitacional, entonces la magnitud de la fuerza gravitacional del peso equivale a la magnitud de su masa. En síntesis, la magnitud de la masa es $78.447\,lbm$ .

La magnitud de la masa del peso es 78.447 libras-masa.

7 0

2 years ago