Answer:
K = -½U
Explanation:
From Newton's law of gravitation, the formula for gravitational potential energy is;
U = -GMm/R
Where,
G is gravitational constant
M and m are the two masses exerting the forces
R is the distance between the two objects
Now, in the question, we are given that kinetic energy is;
K = GMm/2R
Re-rranging, we have;
K = ½(GMm/R)
Comparing the equation of kinetic energy to that of potential energy, we can derive that gravitational kinetic energy can be expressed in terms of potential energy as;
K = -½U
A) The resultant force is 30.4 N at 
B) The resultant force is 18.7 N at 
Explanation:
A)
In order to find the resultant of the two forces, we must resolve each force along the x- and y- direction, and then add the components along each direction to find the components of the resultant.
The two forces are:
at
above x-axis
at
above y-axis
Resolving each force:


So, the components of the resultant are:

And the magnitude of the resultant is:

And the direction is:

B)
In this case, the 15 N is applied in the opposite direction to the 20 N force. Therefore we need to re-calculate its components, keeping in mind that the angle of the 15 N force this time is

So we have:

So, the components of the resultant this time are:

And the magnitude is:

And the direction is:

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It will be traveling exactly 24 miles per hour <span />
Answer:
D
Explanation:
reactants have higher potential energy and energy is absorbed