Mr. Draper asks his class to design a system of gears, strings, and pulleys that will allow him to pull back the classroom's curtains simply by turning a crank at his desk. The system must be built within the following constraints:
It must be made only out of metal gears, metal pulleys, string, and one crank.
It must be strong enough to move the curtains.
It cannot be in the way of students or their desks.
It must take no more than one day to build.

The final design will use which type of energy to perform work on the curtains?
A.
elastic potential energy
B.
gravitational potential energy
C.
thermal energy
D.
kinetic energy

adding a(n) to an electric circuit would increase the magnetic field around a wire;

b. solenoid

a solenoid is a type of electromagnet whose purpose is to generate a controlled magnetic field.

if the purpose of the solenoid is instead to impede changes in the electric current, a solenoid can be more specifically classified as an inductor rather than an electromagnet.

as we probably am aware that our atmosphere or air have various levels, each level has different gasses, and each gas has another porousness. at the point when the light originates from lower porousness to higher penetrability, it alters its course. with the goal that implies that when the light originates from the moon to the earth, it alters it's course a lot more occasions. it essentially implies that the state of the light piece of the moon is changed on the earth.

not copied too! hope this !

joke:

h o h o hope you have a merry christmas!