Answer: The coefficient of kinetic friction is μ = 0.6
Explanation:
For an object of mass M, the weight is:
W = M*g
where g is the gravitational acceleration: g = 9.8m/s^2
And the friction force between this object and the surface can be written as:
F = W*μ
where μ is the coefficient of friction (kinetic if the object is moving, and static if the object is not moving, usually the static coefficient is larger)
In this case, the weight is:
W = 20N
And the friction force is:
F = 12N
Replacing these values in the equation for the friction force we get:
12N = 20N*μ
(12N/20N) = μ = 0.6
The coefficient of kinetic friction is μ = 0.6
I think it would be the scientific method.
B. Kinetic energy plus its potential energy.
Answer:
Speed of wind = 50mi/hr, Speed of plane in still air = 400mi/hr
Explanation:
Let the speed of the wind = Vw,
Speed of the plane in still air = Vsa,
The first trip the average speed of the plane = 1575mi/4.5hours = 350mi/hr
The coming trip the wind behind = 1575mi/3.5hrs = 450
Write the motion in equation form
First trip ( the plane flew into the wind)
Vaverage = Vsa - Vw
350 = Vsa - Vw
Second trip the wind was behind
450 = Vsa +Vw
Adding the two equation
800 = 2Vas
Vas = 800/2 = 400mi/hr
Substitute for Vas into equation 1
350mi/hr = 400mi/hr - Vw
Vw = 400-350 = 50mi/hr
