Answer:

Explanation:
here it is given that the crate is sliding down with constant speed
so we will have

now we can say

so here we have
a = 0
now from Newton's II law we can say that sum of all forces on the system is always product of mass and its acceleration
so here we will have


Just like any other gas or mixture of gases, the gas molecules are
zipping around in all different directions and with a whole range of
different speeds.
Those that happen to be moving at a speed greater than the Earth's
"escape velocity", AND are pointed away from Earth, AND don't hit
any other molecules before they escape, are lost.
With the combination of Earth's escape velocity, and the temperatures,
thickness, and density of the atmosphere, that process happens slowly
enough to have maintained an atmosphere around this planet until now.
Personally, I hope it hangs around for a while longer. But with the constant
increase in temperature that's been going on, you never know . . .
<h3>
Answer:</h3>
<h3>
Explanation:</h3>
_______________
S=3 m²
F=900 N
_______________
p - ?
_______________
p=F/S=900 N / 3 m² = 300 Pa
Power is the amount of work done over a period of time. If you will put that into an equation, the formula of power will be:
P = W/t
Where:
P = power
W=work
t = time
Your problem already provides you with work and time so all you need to do is divide:
P = W/t
P = 50J/30s
P = 1.67 W
Answer:
An example of kinetic energy is a <u><em>car coming to a stop</em></u>
Explanation:
Kinetic energy is the energy that a body or system possesses due to its movement. In physics this energy is defined as the amount of work necessary to accelerate a body of a certain mass and in rest position, until reaching a certain speed. This energy obtained will remain unchanged as long as this body does not vary its speed. That is, kinetic energy measures how many changes an object that is moving can cause.
<u><em>An example of kinetic energy is a car coming to a stop</em></u>. If the car is moving and comes to a stop, there is a change in speed, therefore in movement, eventually producing a change in kinetic energy. This energy depends on the mass of the body, in this case the car, and the speed. As the speed decreases, the kinetic energy will decrease.