Classical mechanics, kinematics, vectors, Newton's laws, work and energy, conservation laws, rotational kinematics.

Prerequisites: Mathematics 2A/3A and Mathematics 2B/3B or Physics 8 or AP Calculus BC Exam score of 5.

4

Units

Optional

Grading

1, 2

Passtime

None

Level Limit

Letters and science

College
GEs Area C Quant Relationships
Unlocks EARTH 100 EARTH 113 ENV S 113 PHYS 22
These majors only phys phycs
WELD D M
David Weld
4.2
12 reviews
AI predicted, based on past grading trends of the course and instructor, class info, and 127 other factors
PHELP1444
R
17:00 PM - 17:50 PM
0 / 35

PHELP1444
R
18:00 PM - 18:50 PM
0 / 35

PHELP1440
R
19:00 PM - 19:50 PM
0 / 35

PHELP1448
F
14:00 PM - 14:50 PM
0 / 35

PHELP1445
F
15:00 PM - 15:50 PM
0 / 35

PHELP1440
F
16:00 PM - 16:50 PM
0 / 35

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Winter 2024 . Banta I C
BRDA 1640
T R
09:30 AM - 10:45 AM
Fall 2024 . Caratelli D
BRDA 1640
M W
15:30 PM - 16:45 PM
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PHYS 21 Bibilashvili Winter 2026 Total: 96
PHYS 21 Johnson C V Fall 2025 Total: 160
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12
4.2
PHYS119A . Weld D M 4 Months Ago

Professor Weld sticks to the textbook and the lectures are all right. The final covers everything over the quarter so it is overwhelming. He would put some harder versions of the typical problems which is fine. But there are always a few thinking problems that make his exams unpredictable and hard if you don't know all of the material indepth.

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PHYS119A . Weld D M 4 Months Ago

He can be very dry but very funny during his lectures. He is very passionate about physics so lectures can be very interesting but he can be monotone at times which can make them boring too. There are very few homework assignments and he doesn't provide study guides or practice for exams. Be ready to study on your own. Otherwise, he is great.

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110B . Weld D M 2 Years Ago

One of the hidden gems in the physics department. Can be dull at times in lecture, but makes up for it with his jokes. His homework is challenging but exams are straightforward, especially since he allows a cheat sheet. He has a strong understanding of EM, which is exemplified by his clear lectures and adeptness at responding to student questions.

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110B . Weld D M 2 Years Ago

Overall the lectures are easy to follow and well prepared. However, the inconsistencies between homeworks and exams are frustrating. In the homework that was due a day before the midterm, there are ~5 questions on stress tensor, but there were none on the midterm. Similar things goes for the final.

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PHYS110A . Weld D M 2 Years Ago

As far as physics profs go, he's pretty good. Lectures are clear and we follow the chapters in the book pretty closely. The material is difficult, so definitely go to office hours when you can, sometimes he will help you get started on a HW problem. You are allowed a cheat sheet on exams which is a lifesaver!

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110B . Weld D M 4 Years Ago

One of the best professor in the physics department in teaching. He knows the content pretty well and can provide great physical intuition and many real-life examples. Have taken his 115C in the fall, which was also delightful. Homework and exams are not hard. This means this course is relatively less stressful. In general, I strongly recommend.

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PHYS 20AL
0 / 24 Enrolled
Experimental Physics
Dirk Bouwmeester 2.7
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19:00 PM - 21:50 PM
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Experimental Physics
Dirk Bouwmeester 2.7
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16:00 PM - 18:50 PM
PHYS 20AL
0 / 24 Enrolled
Experimental Physics
Dirk Bouwmeester 2.7
T
16:00 PM - 18:50 PM
PHYS 20AL
0 / 24 Enrolled
Experimental Physics
Dirk Bouwmeester 2.7
M
19:00 PM - 21:50 PM
PHYS 20AL
0 / 24 Enrolled
Experimental Physics
Dirk Bouwmeester 2.7
M
13:00 PM - 15:50 PM
PHYS 20AL
0 / 24 Enrolled
Experimental Physics
Dirk Bouwmeester 2.7
W
13:00 PM - 15:50 PM