Answer:
K.E = 0.0075 J
Explanation:
Given data:
Mass of the ball = 1.5 kg
radius, r = 50 cm = 0.5 m
Angular speed, ω = 12 rev/min = (12/60) rev/sec = 0.2 rev/sec
Now,
the kinetic energy is given as:
K.E = 
where,
I is the moment of inertia = mr²
on substituting the values, we get

or
K.E = 0.0075 J
The correct answer is C; Bicycles.
Further Explanation:
In major cities, in the United States, have implemented signal lights specifically designed for bicycle riders. The riders also have their own designated bike lanes in many large cities. Drivers in vehicles, are to give the right of way to people on bicycles.
Bicycle riders are to follow the same laws and laws specifically for the riders or they can face fines and tickets.
Learn more about bicycle laws at brainly.com/question/8934107
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I think you can just sub the values in? unless the qn is asking for smth else?
Answer:
Ionic compound.
Explanation:
812° C is a very high melting point. Such high melting points are generally ionic compound. Ionic compounds are have very strong bond between the elements ( electrostatic bond). In order to break this bond, large amount of heat energies are needed. So, they have high melting point. Also, Ionic compound are very good conductors of electricity.