Answer:

Explanation:
The torque of a force is given by:

where
F is the magnitude of the force
d is the distance between the point of application of the force and the centre of rotation of the system
is the angle between the direction of the force and d
In this problem, we have:
, the force
, the distance of application of the force from the centre (0,0)
, the angle between the direction of the force and a
Therefore, the torque is

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Since the mass of the sun and it's temperature are not quite enough to generate nuclear FUSION on their own, quantum tunneling is the primary process by which nuclear fusion occurs in our sun, SOL. FISSION also occurs as a result of this fusion.
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Answer:
The friction force is 250 N
Explanation:
The desk is moving at constant velocity. This means that its acceleration is zero: a = 0. Newton's second law states that the resultant of the forces acting on the desk is equal to the product between mass (m) and acceleration (a):

In this case, we know that the acceleration is zero: a = 0, so also the resultant of the forces must be zero:
(1)
We are only interested in the forces acting along the horizontal direction, since it is the direction of motion. There are two forces acting in this direction:
- the pull, forward, F = 250 N
- the friction force, backward, 
Given (1), we have

So the force of friction must be equal to the pull:

Answer:
El peso del cartel es 397,97 N
Explanation:
La tensión dada en cada segmento del cable = 2000 N
El desplazamiento vertical del cable = 50 cm = 0,5 m
La distancia entre los polos = 10 m
La posición del letrero en el cable = En el medio = 5
El ángulo de inclinación del cable a la vertical = tan⁻¹ (0.5 / 5) = 5.71 °
El peso del letrero = La suma del componente vertical de la tensión en cada lado del letrero
El peso del signo = 2000 × sin (5.71 grados) + 2000 × sin (5.71 grados) = 397.97 N
El peso del signo = 397,97 N.