The kinematics and Newton's second law allow us to find the height from which the block system descends is:
y = 6.54 m
Given parameters
To find
Newton's second law gives a relationship between the net force, the mass, and the acceleration of the body.
∑ F = m a
Where the bold letters indicate vectors, F is the force, m the mass and the acceleration of the body.
Kinematics studies the movement of bodies, looking for relationships between position, velocity and acceleration
y = v₀ t + ½ a t²
In the attached we have a free body diagram of the system, let's write Newton's second law.
T - W₁ = m₁ a
-T + W₂ = m₂ a
Let's solve the system of equations.
W₂ - W₁ = (m₁ + m₂) a
a = [tex]\frac{m_2-m_1}{m_2+m_1} \ g[/tex]
Let's calculate
a = [tex]\frac{2 -4}{ 2 +4} \ 9.8[/tex]
a = -3.27 m / s²
The negative sign indicates that the heaviest body is descending.
Now we can use kinematics to find the height, as the system comes out of rest the initial velocity is zero, when he reaches the ground his height is zero.
y = y₀ + v₀ t + ½ a t²
0= y₀ + 0 +½ a t²
Let's calculate
y₀ = ½ 3.27 2²
y = 6.54 m
In conclusion, using kinematics and Newton's second law we can find the height from which the block system descends is:
y = 6.54 m
Learn more here: brainly.com/question/19818185
