Answer:
0.35
Explanation:
According to Newton's second law;
\sum Fx = ma
Fm - Ff =ma
Fm is the moving force = Wsin theta
Fm = 4(9.8)sin55
Fm = 32.1N
Ff is the frictional force = nmgcos theta
Ff = n(4)(9.8)cos55
Ff = 22.48n
Acceleration a = 6.0m/s²
Substitute the given values into the formula and get the coefficient of friction
32.11-23.48n = 4(6)
32.11-24= 23.48n
8.11 = 23.48
n = 8.11/23.48
n = 0.35
Hence the coefficient of friction is 0.35
As the centripetal force<span> acts upon an </span>object moving <span>in a </span>circle<span> at constant speed, the </span>force<span> always acts inward as the velocity of the </span>object<span> is directed tangent to the </span>circle. ... In fact, whenever the unbalanced centripetal force<span> acts perpendicular to the direction of </span>motion<span>, the speed of the </span>object will<span> remain constant.</span>
<span>The water is clearer, has higher oxygen levels, and freshwater fish such as trout and heterotrophs can be found. In the middle of the river, the width increases, so do the species of aquatic green plants and algae. Toward the mouth of the river, the water becomes murky from all the sediments that it has picked up upstream.<span>
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The speed of the brick dropped by the builder as it hits the ground is 17.32m/s.
Given the data in the question;
Since the brick was initially at rest before it was dropped,
- Initial Velocity;

- Height from which it has dropped;

- Gravitational field strength;

Final speed of brick as it hits the ground; 
<h3>Velocity</h3>
velocity is simply the same as the speed at which a particle or object moves. It is the rate of change of position of an object or particle with respect to time. As expressed in the Third Equation of Motion:

Where v is final velocity, u is initial velocity, h is its height or distance from ground and g is gravitational field strength.
To determine the speed of the brick as it hits the ground, we substitute our giving values into the expression above.

Therefore, the speed of the brick dropped by the builder as it hits the ground is 17.32m/s.
Learn more about equations of motion: brainly.com/question/18486505