Answer:
The final angular velocity is 20rad/s
Explanation:
We are given;
mass, m = 12 kg
radius, r = 0.25 m
Work done;W = 75 J
Moment of inertia of cylinder, I = (1/2) mr²
Thus,
I = (1/2) x 12 x 0.25² = 0.375 kg.m²
Now, from work energy theorem,
Work done = Change in kinetic energy
So, W = KE_f - KE_i
Now, Initial Kinetic Energy (KE_i) = 0
Final Kinetic Energy; KE_f = (1/2)Iω²
So, KE_f = (1/2) x 0.375 x ω²
KE_f = 0.1875 ω²
Now, W = 75 J
Thus,
From, W = KE_f - KE_i, we have;
75 = 0.1875 ω² - 0
75 = 0.1875 ω²
ω² = 75/0.1875
ω² = 400
ω = √400
ω = 20 rad/s
When you heat something of cool it down you don't change the substance you might change the why is looks, but it is still the same substance. For example you cool water to 0 degrees Celsius it turns into ice but it still is two parts hydrogen and one part oxygen H2O. Physical changes will change state and/or form but it will still be what it originally was on the molecular level. Hope that helped.
it will move the object if you apply force, because of that it will stay the same with newton's law.
Change of a liquid to a gas