The shape of a river's stream bed affects the speed and eroding power of a river by influencing the amount of friction between the water flowing through the river and the stream bed below. Friction is the force that opposes the motion of one surface as it moves across another surface. In a river, there is friction between the flowing water and the stream bed beneath it. Where a river is deep, less water comes into contact with the stream bed, so there is less friction. The reduced friction means there is less opposition to the water's motion, so the river flows at a greater speed and has more kinetic energy for erosion. On the other hand, where a river is shallow, more water comes into contact with the stream bed, so there is more friction. The increased friction means there is more opposition to the water's motion, so the river flows at a lesser speed and has less kinetic energy for erosion. Also, the roughness of a stream bed covered with boulders and other obstacles causes the water to flow through the river in a turbulent fashion. This could cause the river to move slower in some cases or erode more in other cases.
The shape of a river’s stream bed affects the speed and eroding power of a river by influencing the amount of friction between the water flowing through the river and the stream bed below. Friction is the force that opposes the motion of one surface as it moves across another surface. In a river, there is friction between the flowing water and the stream bed beneath it. Where a river is deep, less water comes into contact with the stream bed, so there is less friction. The reduced friction means there is less opposition to the water’s motion, so the river flows at a greater speed and has more kinetic energy for erosion. On the other hand, where a river is shallow, more water comes into contact with the stream bed, so there is more friction. The increased friction means there is more opposition to the water’s motion, so the river flows at a lesser speed and has less kinetic energy for erosion. Also, the roughness of a stream bed covered with boulders and other obstacles causes the water to flow through the river in a turbulent fashion. This could cause the river to move slower in some cases or erode more in other cases.
Explanation:
summary of answer:
influencing the amount of friction between the water flowing through the river and the stream bed below.
Scales measure how much something weighs—and they do it by measuring how much force exists between the object you're weighing and planet Earth. Although scales measure force, they give you measurements of mass in kilograms, grams, pounds, or whatever.
The law of reflection states that the angle of incidence is equal to the angle of reflection. Furthermore, the law of reflection states that the incident ray, the reflected ray and the normal all lie in the same plane.
Work is (force applied) x (distance through which the force moves).
Since the suitcase doesn't move up or down during the 15 minutes, no work is done ... zero, zip, nada ... according to the real Physics definition of 'work'.
