The correct option is C.
From the information given above, one can easily conclude that electromagnetic Y is the strongest because, it produces the higher amount of current compare to the other electromagnets. Electromagnet W is the weakest because it produces the lowest amount of current.
By Newton's second law, the net vertical force acting on the object is 0, so that
<em>n</em> - <em>w</em> = 0
where <em>n</em> = magnitude of the normal force of the surface pushing up on the object, and <em>w</em> = weight of the object. Hence <em>n</em> = <em>w</em> = <em>mg</em> = 196 N, where <em>m</em> = 20 kg and <em>g</em> = 9.80 m/s².
The force of static friction exerts up to 80 N on the object, since that's the minimum required force needed to get it moving, which means the coefficient of <u>static</u> friction <em>µ</em> is such that
80 N = <em>µ</em> (196 N) → <em>µ</em> = (80 N)/(196 N) ≈ 0.408
Moving at constant speed, there is a kinetic friction force of 40 N opposing the object's motion, so that the coefficient of <u>kinetic</u> friction <em>ν</em> is
40 N = <em>ν</em> (196 N) → <em>ν</em> = (40 N)/(196 N) ≈ 0.204
And so the closest answer is C.
(Note: <em>µ</em> and <em>ν</em> are the Greek letters mu and nu)
The formula for both is v(t) = v0 + a*t
b) v(8) = 0 + 6m/s^2 *8s = 48 m/s
now we know the beginning (2) and end speed (14), but not the time:
c) 14 = 2 + 1.5*t => t = (14-2)/1.5 = 8 seconds
The ice and how the blades are made
Answer:
d. The magnitude of the work done by the earth on the satellite is non zero
Explanation:
The work done is equal to the product of the force and the distance moved in the direction of the force, the force and the distance act perpendicular to one another, therefore no work is done in the circular motion of the movement of the earth.