1.
Concepts a. If an object is moving, must there be one or more forces acting on it? Briefly explain your answer, citing the appropriate physical law(s). No, it is not necessary for forces to act on an object for it to move. By the First Law, an ob
Midterm II (Physics 3A)
Name_, ID_, Discussion_
Multiple choices (8% each)
1. A h
eavy packing case is pulled by a force F exerted at a 30 angle, and pushed by a
force P exerted horizontally. If the surface is frictionless, the equation of motion of the
p
Physics 3A
- Review for what we must know
Problem Solving Strategies
Conceptualize
Sketch the problem
Draw diagram(s) if necessary
Analyze
List known and unknown quantities
Find the right equation(s)
Finalize
Solve the equations
Give the answer (
1. Units and Vectors (8 points) a. In atomic physics, the Bohr radius a0 of the Hydrogen atom (describing the size of a Hydrogen atom in its ground state) is given by the expression: h a0 = , where me is the mass of the electron, c is the speed of li
Final (Physics 3A)
Name_, ID _, Discussion Section _
Multiple choices (4.0% each)
1. A hot air balloon rises with a constant speed of 5" m s . When it is 30 m above the
ground a rock is dropped from the balloon. How long in s does it take the rock to hit
Physics 3A - Fall 2011
( MWF 3:00-3:50 PM in PSLH 100A)
Dr. R. Wu
RH310G
Phone: 824-7640
e-mail: [email protected]
Office hour:
W 1:30-2:30 pm; M F 4:00-4:40pm
Textbook:
Physics for Scientists & Engineers, by Giancoli (4/e)
Homework assignments on
Mastering Phy
Version A
Student ID:
The following questions are 2 pts each, ignore air resistance, and treat the magnitude of
the acceleration due to gravity as 10 m/s2. Record your answer in the box provided for
credit.
1) You throw a 20 g baseball at 20 m/s. What was
Physics 3A: lecture 2 example
Problem
Consider two male deer that are having a fight
in the woods. They start 20 m apart and run at
each other. Each of them are going at a
constant speed of 5 m/s (relative to the
ground). How long does it take for them to
2014-summer
solution
The following questions are 2 pts each, ignore air resistance, and treat the magnitude of
the acceleration due to gravity as 10 m/s2. Record your answer in the box provided for
credit. Recall that if the question is asking about a vec
Lecture
4/17/12
Quiz results
trying to figure out what equation to use for a problem.
how to tackle larger scaled problems. How to break them down, how to
determine the situation,
being patient and trying to break the problem down into smaller pieces
that
Version A
Student ID:
The following questions are 2 pts each, ignore air resistance, and treat the magnitude of
the acceleration due to gravity as 10 m/s2. Record your answer in the box provided for
credit.
1) You throw a ball horizontally from a height o
Lecture 22
5/25/12
Example 1
You are bouncing on a trampoline that acts as a spring. If
you just stand still on the trampoline without bouncing,
the trampoline is displaced 0.2 m from its equilibrium
state (the trampoline being flat). When you are jumping
Physics 2A 2013
Exam 2 Solution
Please note that the ORDER of the questions was changed on some of the exams. So you
need to compare the WORDING of the question with your exam, not the question
number.
1) A 70 kg cheetah can go from 0 m/s to 30 m/s in 3.0
Lecture 4
4/8/12
Clicker question 1
To turn around when moving, you have to
a) Have zero velocity at some point.
b) Have zero velocity in the original
direction of motion.
c) Both a and b are true
d) Neither a nor b is required if you turn
quickly enough.
Version A
Student ID:
The following questions are 2 pts each, ignore air resistance, and treat the magnitude of
the acceleration due to gravity as 10 m/s2. Record your answer in the box provided for
credit.
1) A 70 kg cheetah can go from 0 m/s to 30 m/s i
Solution
Student ID:
The following questions are 2 pts each, ignore air resistance, and treat the magnitude of
the acceleration due to gravity as 10 m/s2. Record your answer in the box provided for
credit.
1) You throw a ball horizontally from a height of
2014-summer
solution
The following questions are 2 pts each, ignore air resistance, and treat the magnitude of
the acceleration due to gravity as 10 m/s2. Record your answer in the box provided for
credit. Recall that if the question is asking about a vec
You need to lift a 20 kg mass to a height of 5 m. You can either use a rope and pulley to lift it straight up or
to slide it up a frictionless ramp that makes an angle of 30o with the horizontal. Which requires less force?
Which requires less work by the
Solutions Exam 1 2013
The following questions are 2 pts each, ignore air resistance, and treat the magnitude of
the acceleration due to gravity as 10 m/s2. Record your answer in the box provided for
credit.
1) You are running to catch a bus and go from 0.
3A Exam 1 Solutions
The following questions are 2 pts each, ignore air resistance, and treat the magnitude of
the acceleration due to gravity as 10 m/s2. Record your answer in the box provided for
credit.
1) You are driving your car down the road at 20 m/
The following questions are 2 pts each. Please record your answer in the box provided for
credit.
1) Two particles are traveling with the same velocity. They both hit a wall and come to
rest in the same amount of time. If particle A has four times the mas