The gravitational potential energy of the object is 100 J.
Gravitational potential energy stored in an object is the work done in raising the object to a height <em>h</em> against the gravitational force acting on it.
The gravitational force acting on a body is its weight mg, where m is its mass and g, the acceleration due to gravity.
Work done by a force is equal to the product of the force and the displacement made by the point of application of the force.

The weight of the object is given as 20 J and it is raised to a height of 5 m.

The gravitational potential energy of the object is 100 J.
Energy can not be created or destroyed but can change from one form to another.
example: as a roller coaster cart loses height the more speed it gains, the potential energy is transferred into kenetic energy
<span>The answer is letter D.
The most important step in formulation a scientific inquiry is to first formulate a question. All answers sprung from a question that scratched the mind. Experimentation is not possible without the need to question, with this, the drive to find the answers is what motivates scientists or people involved in an experiment to find the answers that would suffice their curiosity. Questions are the basis of all the other choices above and is the most crucial step in the scientific inquiry.<span>
</span></span>
S orbital.
Group 1 elements have a general configuration
, where n represents the highest occupied Principal Energy Level. For example, Lithium has the valence configuration
whereas Cesium has
. Both of them belong to Group 1 of Periodic Table.
Group 2 elements have a general configuration of
. For example, Magnesium has
as its outer shell configuration while Strontium has the same as
.
We see that in both the cases, the outermost S orbital is being filled.
Answer:
Object should be placed at a distance, u = 7.8 cm
Given:
focal length of convex lens, F = 16.5 cm
magnification, m = 1.90
Solution:
Magnification of lens, m = -
where
u = object distance
v = image distance
Now,
1.90 = 
v = - 1.90u
To calculate the object distance, u by lens maker formula given by:
u = 7.8 cm
Object should be placed at a distance of 7.8 cm on the axis of the lens to get virtual and enlarged image.