Answer
18,000
Why?
KE=(1/2)(2000)(18)
Ke=18,000
The radius of the circular motion at the given speed is 1.56 m.
The given parameters;
- <em>speed of the rock, v = 2.5 m/s</em>
- <em>acceleration of the rock, a = 4 m/s²</em>
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The radius of the circular motion is calculated by using centripetal acceleration formula as follows;

Thus, the radius of the circular motion at the given speed is 1.56 m.
Learn more about centripetal acceleration here: brainly.com/question/79801
Answer:
Explanation:
Given
No of atoms of hydrogen 
Temperature of room 
Thermal energy of the atoms is given by

where k=boltzmann constant


Hence the energy of the atoms is 
Answer:

Explanation:
The density of an object is given by

where
m is the mass of the object
V is its volume
In this problem,
m = 42 kg
V = 22 m^3
Substituting into the equation, we find the object's density:

Fc=mv^2/r so we get
2000kg*(25m/s)^2/(80m)= 15625N of force
hope this helps! Thank You!!