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Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
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Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
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Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
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The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
2. Lenses
Lenses are made of transparent
materials, like glass or plastic.
Each of a lens’ two faces is part of a
sphere and can be convex or concave
If a lens is thicker at the center than the
edges, it is a convex, or converging, lens
since parallel rays will be converged to
meet at the focus.
A lens which is thinner in the center
than the edges is a concave, or diverging,
lens since rays going through it will be
spread out.
Convex
(Converging) Lens
Concave
(Diverging) Lens
3. Lenses and Images
Light rays that enter a converging lens parallel to its axis bend
to meet at a point called the focal point.
The distance from the center of the lens to the focal point is
called the focal length.
The optical axis usually goes through the center of the lens.
5. The image formed by a lens
A lens can form a virtual image just as a mirror does.
Rays from the same point on an object are bent by the lens so
that they appear to come from a much larger object.
6. A converging lens can also form a real image.
In a real image, light rays from the object actually come back
together.
The image formed by a lens
7. Drawing ray diagrams
A ray diagram is the best way to understand what type of
image is formed by a lens, and whether the image is
magnified or inverted.
These three rays follow the rules for how light rays are bent
by the lens:
1. A light ray passing through the center of the lens is not
deflected at all (A).
2. A light ray parallel to the axis passes through the far focal
point (B).
3. A light ray passing through the near focal point emerges
parallel to the axis (C).
8. Convex Lens: Object Beyond 2F
•• • •F F 2F2F
object
image
The image formed when
an object is placed
beyond 2F is located
behind the lens between
F and 2F. It is a real,
inverted image which is
smaller than the object
itself.
Experiment with this diagram
9. Convex Lens: Object Between 2F and F
•• • •F F 2F2F
object
image
The image formed
when an object is
placed between 2F and
F is located beyond 2F
behind the lens. It is a
real, inverted image,
larger than the object.
10. Convex Lens: Object within F
•• • •F F 2F2F
object
image
The image formed when an object is placed in front of F is
located somewhere beyond F on the same side of the lens as
the object. It is a virtual, upright image which is larger than
the object.
convex lens used as a magnifier
11. Concave Lens Diagram
•• • •F F 2F2F
object
image
No matter where the object is placed, the image will be on the same
side as the object. The image is virtual, upright, and smaller than
the object with a concave lens.
Experiment with this diagram
12. Sign convention for spherical lenses
The sign convention for spherical lenses is the same as in
spherical mirrors except that the distances are measured from the
optical centre (O).
The focal length of a convex lens is positive ( + ve ) and the
focal length of a concave lens is negative ( - ve ).
Direction of incident light
Distance towards the left (- ve )
Height
downwards ( - ve )
Height
upwards ( + ve )
Convex lens
Object
Image
O
Distance towards the right ( + ve )
13. Thin lens formula
The thin lens formula is a mathematical way to do ray
diagrams with algebra instead of drawing lines on graph
paper.
1 + 1 = 1
o i f
focal
length (cm)
Image distance
(cm)
Object
distance
(cm)
15. Derivation of Lens Formula (Convex Lens)
Let AB represent an object placed at right angles to the principal
axis at a distance greater than the focal length f of the convex lens.
The image A1B1 is formed beyond 2F2 and is real and inverted.
OA = Object distance = u
OA1 = Image distance = v
OF2 = Focal length = f
C C
16. OAB and OA1B1 are similar
A1B1
A B
=
O A1
O A
------------------- (1)
Similarly , OCF2 and F2A1B1 are similar
A1B1
O C
=
F2A1
O F2
C C
But we know that OC = AB
the above equation can be written as
17. C C
A1B1
A B
=
F2A1
O F2
------------------- (2)
From equation (1) and (2), we get
O A1
O A
= F2A1
O F2
= OA1 – OF2
O F2
v
-u
= v – f
f
Or
v f = - u v + u f ------------------- (3) Dividing Both side by uvf
1
u
=
-1
f
+
1
v
Or
1
f
=
1
v
1
u
–
18. The magnification M of an image is the ratio of the height of
the image to the height of the object:
M =
Image height
Object height
This number is a dimensionless ratio (a length over a length)
and does not have any units
Rule: The magnification factor M of a lens is always positive
and given by:
M =
v
u
Image height
Object height
Magnification of a lens
19. Power of a lens
The power of a lens is the reciprocal of its focal length
The SI unit of power is dioptre (D).
1 dioptre is the power of a lens whose focal length is 1 meter.
The power of a convex lens is positive ( + ve ) and the power of a
concave lens is negative ( - ve ).
)(
1
mf
P
P
f
1
0r
20. Optical Systems
An optical system is a collection of mirrors, lenses, prisms,
or other optical elements that performs a useful function
with light.
Characteristics of optical systems are:
– The location, type, and magnification of the image.
– The amount of light that is collected.
– The accuracy of the image in terms of sharpness, color,
and distortion.
– The ability to change the image, like a telephoto lens on a
camera.
– The ability to record the image on film or electronically.
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