We can answer this using
the rotational version of the kinematic equations:
θ = θ₀ + ω₀t + ½αt²
-----> 1
ω² = ω₀² + 2αθ -----> 2
Where:
θ = final angular displacement = 70.4 rad
θ₀ = initial angular displacement = 0
ω₀ = initial angular speed
ω = final angular speed
t = time = 3.80 s
α = angular acceleration = -5.20 rad/s^2
Substituting the values
into equation 1:
70.4 = 0 + ω₀(3.80)
+ ½(-5.20)(3.80)²
ω₀ = (70.4
+ 37.544) / 3.80
ω₀ = 28.406
rad/s
Using equation 2:
ω² = (28.406)² + 2(-5.2)70.4
ω = 8.65 rad/s
Answer:8.65
Explanation:
70.4 = 0 + ω₀(3.80) + ½(-5.20)(3.80)²
ω₀ = (70.4 + 37.544) / 3.80
ω₀ = 28.406 rad/s
Using equation 2:
ω² = (28.406)² + 2(-5.2)70.4
ω = 8.65 rad/s
