Answer:
Mechanical waves need matter to transfer energy while electromagnetic waves do not. ... Waves change direction when they move from one material into another (matter) through the process of refraction. The wave will change direction when the speed of the wave changes.
The heat of fusion for water is the amount of energy needed for water to <span>melt. (c)</span>
Answer:
if one bulb burns out the other bulbs will also turn off because they are connected to each other.
Answer:
The mechanical advantage of a machine is the ratio of the load (the resistance overcome by a machine) to the effort (the force applied). For an ideal (without friction) mechanism, it is also equal to: There is no unit for mechanical advantages since the unit for both input and output forces cancel out.
Explanation:
Answer:
F > W * sin(α)
Explanation:
The force needed for the box to start sliding up depends on the incline (α).
The external forces acting on the box would be the weight, the normal reaction and the lifting force that is applied to make it slide up.
These forces can be decomposed on their normal and tangential (to the slide plane) components.
The weight will be split into
Wn = W * cos(α) (in normal direction)
Wt = W * sin(α) (in tangential direction)
The normal reaction will be alligned with the normal axis, and will be equal to -Wn
N = -W* cos(α) (in normal direction)
To mke the box slide up, a force must be applied, that is opposite to the tangential component of the weight and at least a little larger
F > |-W * sin(α)| (in tangential direction)
