Download Clicker question 29-1

Clicker question 29-1
The angular momentum of a freely rotating disk around its center is Ldisk.
You toss a block horizontally onto the disk along the direction shown. The
block lands on the disk and rotates with it. The magnitude of the total
angular momentum of the disk-block system after the collision
a) 
b) 
c) 
d) 
e) 
is greater than Ldisk in Case 1.
is greater than Ldisk in Case 2.
is less than Ldisk in Case 1.
is less than Ldisk in Case 2.
is equal to Ldisk in Case 1 and Case 2.
Case 1
Case 2
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Clicker question 29-2
Two different spinning disks have the same angular
momentum, but disk 1 has more kinetic energy than
disk 2. Which one has the bigger moment of inertia?
a)  Disk 1
b)  Disk 2
c)  Not enough information is given.
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Clicker question 30-1
Five homogeneous planets have relative masses and sizes as
shown in the figure. Planets 2, 4, and 5 have exactly twice the
radius of 1 and 3. A body of mass m would weigh least on which
planet?
a) 
b) 
c) 
d) 
e) 
1
2
3
4
5
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Clicker question 30-2
Which is stronger, earth’s pull on the moon, or the
moon’s pull on earth?
a) 
b) 
c) 
d) 
e) 
The earth pulls harder on the moon.
The moon pulls harder on the earth.
They pull on each other equally.
There is no force between the earth and the moon.
It depends upon where the moon is in its orbit at that time.
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Clicker question 33-1
As a satellite falls into a lower orbit (without using its
engine), its speed
a) 
b) 
c) 
d) 
e) 
decreases.
is unchanged.
increases.
depends on the mass of the satellites.
cannot be determined.
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Clicker Question FR 1
In which segment is the acceleration the highest?
a) 
b) 
c) 
d) 
e) 
A
B
C
All tie (non zero)
All tie (0)
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Clicker Question FR 2
In case 1, a block is sliding up a rough incline after you kicked it up
along the incline. In case 2, the same block is sliding down the
same incline after you nudged it. In which case is the total
acceleration of the block greater while it is sliding without you
touching it?
a)  Case 1
b)  Case 2
c)  Same in case 1 and 2
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Clicker Question FR 3
Suppose you are pushing horizontally on a box with a mass m that
is sitting on a rough horizontal surface. If the box does not move,
what is the frictional force by the surface on the box? The
coefficient of static friction between the surface and the box is µ.
a)  mgµ
b)  0
c)  Not enough information is given
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Clicker Question FR 4
Suppose a projectile with a mass m is fired from the
ground level with an initial speed of v0, and eventually
returns to the same level. During its entire flight, how
much work is done on the projectile by the earth?
a)  Not enough information is given because it depends on the
maximum height the projectile reaches.
b)  0
c)  ½mv02
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Clicker Question FR 5
A bomb is sitting at rest at the origin on a frictionless
surface. It explodes into two pieces of equal mass. If
one piece is at x = 5m, 2 seconds after the explosion,
where is the other piece at the same time?
a)  Who knows!
b)  x = -5 m
c)  x = -10 m
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Clicker question FR 6
Two blocks of different masses are connected by a
massless rope that goes over a pulley (Atwood
machine). If the moment of inertia of the pulley about its
axis is not negligible, is the tension in the entire rope
constant?
a)  Yes
b)  No
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Clicker question FR 7
An apple and an orange are separated by some distance. The
gravitational force between the two is Fao. If you double the mass of
the apple, and double the separation, what is the gravitational force
between the apple and the orange?
a) 
b) 
c) 
d) 
e) 
2Fao
½Fao
4Fao
¼Fao
Fao
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Clicker Question FR 8
An apple and an orange are separated by some distance. The
gravitational potential energy between the two is Uao. If you double
the mass of the apple, and double the separation, what is the
gravitational potential energy between the apple and the orange?
a) 
b) 
c) 
d) 
e) 
2Uao
½Uao
4Uao
¼Uao
Uao
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Clicker Question FR 9
A ball fired vertically upward from the surface of the earth at 95% of
the escape speed. Which of the following physical laws can you
apply to this situation to effectively calculate the maximum height
above the earth’s surface the ball will rise?
a) 
b) 
c) 
d) 
e) 
Conservation of linear momentum
Conservation of angular momentum
Conservation of mechanical energy
Newton’s 2nd law (Net force and acceleration)
Newton’s 3rd law (force pair)
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Clicker Question FR 10
Planet X orbits around Star Y. The mass of Star Y is 4 times that of
the sun, and the orbital radius of Planet X is 9 times that of the
earth. What is the orbital period of Planet X?
a) 
b) 
c) 
d) 
e) 
9 / 4 earth years
27 / 2 earth years
3 / 2 earth years
9 earth years
Not enough information is given.
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