If the satellite doesn't have little rocket engines or other thrusters on it, AND it stays far enough from Earth that it doesn't have to plow through any air molecules, AND no pieces break off of it and drift away, AND there are no hamsters inside it running on treadmills connected to external thrusters, then there's no way for it to gain or lose energy, and its total energy remains constant.
Some of its energy is always changing, either from potential to kinetic or from kinetic to potential, as its distance from Earth changes. But the total stays constant.
Answer:
Chemical energy, Energy stored in the bonds of chemical compounds. Chemical energy may be released during a chemical reaction, often in the form of heat; such reactions are called exothermic.
Answer:
<u>6.87 ft/s</u> is the rate at which the top of ladder slides down.
Explanation:
Given:
Length of the ladder is, 
Let the top of ladder be at height of 'h' and the bottom of the ladder be at a distance of 'b' from the wall.
Now, from triangle ABC,
AB² + BC² = AC²
Differentiating the above equation with respect to time, 't'. This gives,
In the above equation the term 
is the rate at which top of ladder slides down and 
is the rate at which bottom of ladder slides away.
Now, as per question, 
Plug in 
in equation (1) and solve for 
. This gives,
Now, plug in all the given values in equation (2) and solve for
Therefore, the rate at which the top of ladder slide down is 6.87 ft/s. The negative sign implies that the height is reducing with time which is true because it is sliding down.
Answer:
15.7 N
Explanation:
Draw a free body diagram. The block has four forces acting on it. Gravity pulling down, normal force pushing perpendicular to the plane, friction pointing up the plane, and applied force F pushing up the plane.
Sum of the forces normal to the plane:
∑F = ma
N − mg cos θ = 0
N = mg cos θ
Sum of the forces parallel to the plane:
∑F = ma
Nμ + F − mg sin θ = 0
F = mg sin θ − Nμ
Substituting:
F = mg sin θ − mgμ cos θ
F = mg (sin θ − μ cos θ)
Given mg = 87.0 N, θ = 24.1°, and μ = 0.25 (because the block is not moving):
F = 87.0 N (sin 24.1° − 0.25 cos 24.1°)
F = 15.7 N
