Answer:
the speed of the object has become constant.
Explanation:
At terminal velocity, air resistance equals in magnitude the weight of the falling object. Because the two are oppositely directed forces, the total force on the object is zero, and the speed of the object has become constant.
Given :
- Acceleration (a) = 3.7 m/s²
weight is equal to :
Weight of the object is 0.37 Newtons ~
Correct choice is B
Answer:
k = 101.2 N / m
Explanation:
For this exercise we can use the relationship between work and energy
W = ΔK (1)
Where the work of the friction force is
W = fr x cos θ
As the friction force opposes the movement, the angle is 180º, so the kinetic product remains
W = - fr x
The friction force is given by the equation
fr = μ N
Let's use Newton's second law
Axis y
N - W = 0
N = W
We substitute
fr = μ mg
So the work is
W = - μ m g x
On the other hand, the variation in energy is
ΔEm = Em_final - Em_inicial
ΔEm = ½ k x² - ½ m v²
We substitute in our initial equation 1
-μ m g x = ½ k x² - ½ m v²
k = 2m / x² (- μ g x + ½ v²)
k = 2 2.00 / 0.190² (- 0.660 9.8 0.190 + ½ 2.07²)
k = 101.2 N / m