Explanation:
Friction occurs because no surface is perfectly smooth. Rougher surfaces have more friction between them. Heavier objects also have more friction because they press together with greater force. Friction produces heat because it causes the molecules on rubbing surfaces to move faster and have more energy.
Answer:

Explanation:
m = Mass of bungee jumper = 55 kg
g = Acceleration due to gravity = 
h = Height at the bottom = 40 m
k = Spring constant
x = Displacement of bungee cord = 25 m
Applying the principle of conservation of energy to the system we have

The spring constant of the bungee cord is
.
Answer:
0 degrees
Explanation:
Let
are two forces. The resultant of two forces acting on the same point is given by :

Where
is the angle between two forces
When
i.e. when two forces are parallel to each other,


When
i.e. when two forces are parallel to each other,


When
i.e. when two forces are parallel to each other,


It is clear that the resultant of two forces acting on the same point simultaneously will be the greatest when the angle between them is 0 degrees. Hence, this is the required solution.
Answer:
d. No, porque la ecuación de trabajo lo define.
Explanation:
En Física, el trabajo realizado se puede definir como la cantidad de energía transferida cuando un objeto o cuerpo se mueve a lo largo de una distancia debido a la acción de una fuerza externa.
Matemáticamente, el trabajo realizado viene dado por la fórmula;
<u>Dónde;</u>
- W es el trabajo realizado.
- F representa la fuerza que actúa sobre un cuerpo.
- d representa la distancia recorrida por el cuerpo.
Por lo tanto, podemos deducir de la definición de trabajo y su fórmula que el trabajo se realiza cuando un objeto (cuerpo) se mueve una distancia o experimenta cualquier forma de desplazamiento mientras transfiere energía.