The vector sum of forces acting on a non-accelerating object equals zero.
equation form: ΣF = 0
Uniform velocity means no Net force and therefore no acceleration. Acceleration only happens when the velocity changes.
<span>We can answer this using
the rotational version of the kinematic equations:</span><span>
θ = θ₀ + ω₀<span>t + ½αt²
-----> 1</span></span>
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:<span>
70.4 = 0 + ω₀(3.80)
+ ½(-5.20)(3.80)² </span><span>
ω₀ = (70.4
+ 37.544) / 3.80 </span><span>
ω₀ = 28.406
rad/s </span><span>
Using equation 2:
ω² = (28.406)² + 2(-5.2)70.4
ω = 8.65 rad/s
</span>
Answer:
a)
, b) 
Explanation:
a) The final velocity of the 13.5 g coin is found by the Principle of Momentum Conservation:

The final velocity is:

b) The change in the kinetic energy of the 13.5 g coin is:
![\Delta K = \frac{1}{2}\cdot (13.5\times 10^{-3}\,kg)\cdot \left[(11.9\times 10^{-2}\,\frac{m}{s} )^{2}-(0\,\frac{m}{s} )^{2}\right]](https://tex.z-dn.net/?f=%5CDelta%20K%20%3D%20%5Cfrac%7B1%7D%7B2%7D%5Ccdot%20%2813.5%5Ctimes%2010%5E%7B-3%7D%5C%2Ckg%29%5Ccdot%20%5Cleft%5B%2811.9%5Ctimes%2010%5E%7B-2%7D%5C%2C%5Cfrac%7Bm%7D%7Bs%7D%20%29%5E%7B2%7D-%280%5C%2C%5Cfrac%7Bm%7D%7Bs%7D%20%29%5E%7B2%7D%5Cright%5D)
