A60 kg crate is dragged across a floor by pulling on a rope attached to the crate and inclined 18° above the horizontal. (a) if the coefficient of static friction is 0.51, what minimum force magnitude is required from the rope to start the crate moving? (b) if μk = 0.26, what is the magnitude of the initial acceleration (m/s^2) of the crate?

Explanation:

Given

mass of crate=60 kg

inclination

Suppose Force applied by rope is F

F=181.70+285.20=466.9 N

(b)=0.26

here

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.

truck y has a greater velocity than truck x.