It was Niels Bohr who proposed it
Answer:
W = 650 [kJ]
Explanation:
The definition of work is denoted by the product of force by the distance traveled by the body, this distance traveled corresponds to the direction of the force.
In this case we have:
d = distance = 2.6[km] = 2600 [m]
F = force = 250 [N]
W = F*d = 250 * 2600 = 650000 [J] or 650 [kJ]
b. describes it best because a form of molten cools down and makes igneous rock. Good luck! Please mark me brainliest!
Answer:
<em>2.78m/s²</em>
Explanation:
Complete question:
<em>A box is placed on a 30° frictionless incline. What is the acceleration of the box as it slides down the incline when the co-efficient of friction is 0.25?</em>
According to Newton's second law of motion:

Where:
is the coefficient of friction
g is the acceleration due to gravity
Fm is the moving force acting on the body
Ff is the frictional force
m is the mass of the box
a is the acceleration'
Given

Required
acceleration of the box
Substitute the given parameters into the resulting expression above:
Recall that:

9.8sin30 - 0.25(9.8)cos30 = ax
9.8(0.5) - 0.25(9.8)(0.866) = ax
4.9 - 2.1217 = ax
ax = 2.78m/s²
<em>Hence the acceleration of the box as it slides down the incline is 2.78m/s²</em>