Answer:

Explanation:
A closed system is a system where exists energy interactions with surroundings, but not mass interactions. If we neglect any energy interactions from boundary work, heat, electricity, magnetism and nuclear phenomena and assume that process occurs at steady state and all effects from non-conservative forces can be neglected, then the equation of energy conservation is reduce to this form:
(1)
Where:
- Change in kinetic energy of the system, measured in joules.
- Change in gravitational potential energy of the system, measured in joules.
If we know that
and
, then we get the following equation:
(2)
Where
and
stands for initial and final states of each energy component.
Hence, the right answer is 
Wood is a bad conductor of heat. The drilling process involve heat generation between the drill and the wooden material that can not be dissipated away easily. With deep drilling the drill may get so hot that the chips come out in a state of smoking coal.<span>
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Answer:
Explanation:
Gravitational force between two objects having mass m₁ and m₂ at a distance R
F = G m₁ m₂ / R²
Force between baby and father F₁ = 6.67x10⁻¹¹ x 4.1 x 120 / .18²
= 1.01 x 10⁻⁶ N
b )
Force between baby and Jupiter
F₂ = 6.67x10⁻¹¹ x 1.9x 10²⁷ x 4.1 / ( 6.29 x 10¹¹ )²
= 1.31 x 10⁻⁶ N
c )
Ratio = 1.01 / 1.31
= .77
Contour lines are lines that signifies the elevation on a mountain or hill