Physics Lab – I Problems
1.)
A series of wrenches of different lengths is used on a hexagonal bolt, as shown below. Which
combination of wrench length and Force applies the greatest torque to the bolt?
2.)
A certain star, of mass m and radius r, is rotating with a rotational velocity ω . After the star collapses,
it has the same mass but with a much smaller radius. Which statement below is true?
a. The star's moment of inertia I has decreased, and its angular momentum L has increased. b. The star's
moment of inertia I has decreased, and its angular velocity ω has decreased.
c. The star's moment of inertia I remains constant, and its angular momentum L has increased.
d. The star's angular momentum L remains constant, and its rotational kinetic energy has decreased.
e. The star's angular momentum L remains constant, and its rotational kinetic energy has increased
3.) A simple pendulum has a frequency of 0.2 Hz on Earth. It is brought to Mars where g is 38% of its value on
Earth. What will be the pendulum’s frequency on Mars?
A. 0.12 Hz.
B. 0.2 Hz.
C. 0.08 Hz.
D. 0.52 Hz.
E. 0.32 Hz.
4-) A simple pendulum has a period T on Earth. If it were used on Planet X, where the acceleration due to
gravity is 3 times what it is on Earth, its period would be:
A) T/3 B) 3T C) T D) (3)0,5T E) T/ (3)0,5
5-) What will be happen, when a ring and a disc which are equal diameter and equal mass (inertia) will drop in
the same time on a inclined plane. (Note that: Iring > I disc)
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6.) Calculate the angular momentum of disk about center of mass, and disk about diameter. [I 1 = (1/2)Mr2, I2 =
(1/4)Mr2, 1 = 2 = 10 rad/s) ]
7.) A ball is thrown horizontally from a heigh “h” with initial speed V0. Find the V0 with only using g, L, and .
8.) Match the true definition with the true explanation.
Definition
Explanation
1-
Frequency
Matching
A - the resistance an object has to a change in its state
of motion.
1-?
B- It is a vector quantity that represents the product of a
body's rotational inertia and rotational velocity about a
particular axis.
C - is the mass property of a rigid body that determines
the
torque
needed
for
a
desired angular
acceleration about an axis of rotation.
D – An object at rest stays at rest and an object in
motion stays in motion with the same speed and in the
same direction unless acted upon by an unbalanced
force.
2-?
5- Period
E- it is the number of occurrences of a repeating event
per unit time.
5-?
6 - Moment of inertia
F- the time taken for one full oscillation
6-?
7 - Diffraction
G – it refers to various phenomena which occur when a
wave encounters an obstacle or a slit. In classical
physics, the
phenomenon is described as
the interference of waves according to the Huygens
Fresnel principle
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2- Newton's first law of
motion
3 - Angular momentum
4- Inertia
2
3-?
4-?
-?
8) A careless student completed an experiment (horizontal shoot) and measured x=5m, y0=5m. Then he
calculated the initial velocity of ball is 5 m/s. But the real velocity value is 3 m/s. What mistakes may this boy
do? Calculate and review the experiment with yourself. Which measurements should be wrong or true…? What
could be the true values of x or y0 or both of them? (g = 10 m/s2)
Measurements:
y0= 5 m, x= 5 m
y0
x
9)
10)
The graph shows the velocity of a particle as a function of time. According to the graph
a-) the time interval between 0-5 seconds, the object’s velocity is ________
b-) the time interval between 0-5 seconds, the object’s acceleration is ________
c-) the time interval between 5-8 seconds, the object’s acceleration is ________
d-) the time interval between 5-8 seconds, the object’s velocity is ________
e-) the time interval between 8-14 seconds, the object’s velocity is ________
f-) the time interval between 8-14 seconds, the object’s acceleration is ________
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11) Two balls, projected at different times so they don't collide, have trajectories A and B, as shown below.
Which statement is correct?
a.
v0B must be greater than v0A.
b. Ball A is in the air for a longer time than ball B.
c. Ball B is in the air for a longer time than ball A.
d. Ball B has a greater acceleration than ball A.
e. Ball A has a greater acceleration than ball B.
12.) The following measurements were taken in an experiment. T (s) is period of a simple pendulum, and L (m)
is height of it. Answer the questions about given graphics.
a) Which quantity should be on the x-axis, write on the graph.
b) Which quantity should be on the y-axis, write on the graph.
c) According to the given formula (y=….) If A =2,0001  what is the unit of A?
d) If B= 0,5077  what is the SI unit of B?
e) Write the general form of the equation with using A, B, T, L
L(m)
T(s)
0,5
1,42
0,6
1,55
0,75
1,74
0,85
1,85
0,9
1,90
1,3
2,29
1,7
2,62
2,1
2,91
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