The atomic number of an element is ?

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The atomic number of an element is
A. The number of neutrons in the nucleus of the atom
B. The number of protons in the nucleus of the atom
C. The number of electrons in the atom
D.
818-781-1200
Miller indices are used to
A. Define a plane in a crystal structure
B. Define a direction in a unit cell
C. Define a volume in a crystal lattice
D. Determine the direction in which the stock market is heading
Diffusion is the mechanism by which
A. Electrons move from one energy level to another
B. Atoms bond molecularly with each other
C. Matter is transported through matter
D.
You forget everything when taking a test
Materials Engineering is the
A. Applied knowledge of materials
B. Basic knowledge of materials
C. The study of materials
D. Scientific approach to shopping at the mall
The Body Centered Cubic crystal structure has
A. Four atoms per unit cell
B. One atom per unit cell
C. Two atoms per unit cell
D. Only Walls and windows
Materials which contain a large amont of Iron are known as
A. Steels
B. Ferrous metals and alloys
C. Stainless steels
D. Cars
Avagadro’s number is
A. Equal to the number of electrons in an atom
B. 2,875,932
C. The number of atoms in one mole of an element
D. unlisted
The Critical Radius is
A. The minimum size of a particle for solidification to begin
B. The distance between the nucleus and the furthest electron in an atom
C. The distance between the nucleus and the closest electron in an atom
D. All of the above
Line defects in a crystal structure are known as
A. Cracks
B. Dislocations
C. Scratches
D. Broken glass
Composite materials consist of
A. A mixture of two or more materials
B. Only light weight plastics
C. Multiple phases
D. Only liquids

What is the approximate radius of a nucleus? (b) Approximately what is the value of A for a nucleus whose radius is 3.0 x 10-15m?

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2) What is the approximate radius of a nucleus?
(b) Approximately what is the value of A for a nucleus whose radius is 3.0 x 10-15m?
3) Calculate the binding energy per nucleon for a nucleus.
4)
5) Polonium-214 can decay by alpha decay.
a) The product of its decay has how many fewer protons the polonium-214? b) Write the nuclear equation for this decay.
6) Write the nuclear equation for the decay of ? If there are any alpha, beta or gamma particles created what is their maximum kinetic energy created?
7) Francium-223 () has a half-life of 21.8 min.
a) How many nuclei are initial present in a 25.0 mg sample? b) How many nuclei are present 1h and 49 min later?
8) What is the activity of a sample of that contains 8.9 x 1022 nuclei?

Q1) Suppose a person unwisely drives 75 mph (uniform speed) in a 55 mph zone and passes a police car going 55 mph in the same direction. If the police officer begins constant acceleration at the instant he is passed and increases his car’s velocity to 80 mph in 4 seconds, how long does it take him to be even with the pursued car?

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Q1) Suppose a person unwisely drives 75 mph (uniform speed) in a 55 mph zone and
passes a police car going 55 mph in the same direction. If the police officer begins
constant acceleration at the instant he is passed and increases his car’s velocity to 80 mph
in 4 seconds, how long does it take him to be even with the pursued car?
Q2) The position coordinate of a particle which is confined to move along a straight line
(say, X-axis) is given by s = (-2+3t)e –0.5t
, where s is measured in meters from a
convenient origin and t is in seconds. Figure below depicts the s-t graph of the particle’s
motion.
a) Compute the net displacement of the particle from t = 0.5 sec to t = 7.5 sec.
b) What are the average speed and the average velocity of the particle from t = 0 sec to t
= 10 sec?
c) What is the instantaneous velocity of the particle at time t = 5 sec? What is the
instantaneous speed of the particle at t = 5 sec?
d) What is the average acceleration of the particle from t = 0 sec to t = 10 sec?
e) What is the instantaneous acceleration of the particle at t = 7 sec?
Q3) A 200-gram ball is tossed straight up with an initial speed of 10 m/s from a window
located 20 m above the ground. Determine
a) the velocity v and elevation y of the ball above the ground at any instant
b) the highest elevation reached by the ball and the time it took to reach that point c) the time when the ball will hit the ground and the corresponding velocity d) the acceleration of the ball when it is at the highest point and when it is just about
to hit the ground
Draw v-t and y-t graphs.
Q4) A projectile is launched from A with the initial conditions shown in the figure.
Determine how far down the incline the projectile lands (i.e. find L). Also, calculate the total
time of flight and the velocity with which the projectile impacts point B. [g = 10 ms -2
] (Hint:
Fix the standard Cartesian system at A and use it to express the coordinates of B in terms
of L]. Ignore drag.
Q5) With what minimum horizontal velocity u should the boy throw a ball from point A so
that it just clears the obstruction at B.? Assume the wind gives the ball an additional uniform
acceleration in the direction shown. [g = 10 ms -2
]
Q6) The aerodynamic resistance to motion of a car is nearly proportional to the square of
its velocity. Additional friction resistance is constant, so that the acceleration of the car
when coasting under braking may be written as a = -C1-C2v 2 , where C1 = 2 m/s
2 , C2 =
0.004 m -1
. If the car has an initial velocity v0 = 60 mph, when the engine is disengaged,
i) find the distance D required for the car to coast to a stop, and ii) find the time it takes to come to a halt.
120 m/s
40°
800 m 20°
L
u A
B
26 m
14 m
40 m
Acceleration due to wind,
1 ms -2
g
g
A
B
Q7) Jill shoots an arrow from the top of a tower with a speed of 10 m/s. The height of the
tower is 50 meters.
a) At what angle should Jill launch her arrow to maximize her range of shot? b) Compute this range (i.e. distance from the base of tower where the arrow lands).
Repeat a) and b) assuming Jill is standing on ground (i.e. at the base of the tower).
Take g = 10 m/s 2 . Neglect air drag.
Q8) An elevator starts from rest and rises 40 m to its maximum velocity in T seconds
with the acceleration record shown in the figure below. Determine a) the time T, b) the
maximum velocity, c) the velocity and position of the elevator at t = T/2.
T/3 T
0.6
a (m/s
2 )
t (s)

Two identical balls are at rest and side by side at the top of a hill. You let one ball, A, start rolling down the hill. A little later you start the second ball, B, down the hill by giving it a shove. The second ball rolls down the hill along a line parallel to the path of the first ball and passes it. At the instant ball B passes ball A:

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Two identical balls are at rest and side by side at the top of a hill. You let one ball, A, start rolling down the hill. A little later you start the second ball, B, down the hill by giving it a shove. The second ball rolls down the hill along a line parallel to the path of the first ball and passes it. At the instant ball B passes ball A:
Question 22 options:
[removed]
1)
it has the same position and the same velocity as A.
[removed]
2)
it has the same position and the same acceleration as A.
[removed]
3)
it has the same velocity and the same acceleration as A.
[removed]
4)
it has the same displacement and the same velocity as A.
[removed]
5)
it has the same position, displacement and velocity as A.
Save
Question 23 (1 point)
Question 23 Unsaved
When starting from rest at the bottom of a straight road with constant upward slope, Joan bicycles to the top 50.0 s ahead of Sally, whose travel time is 5.00 minutes. What is the ratio of Joan’s acceleration to Sally’s acceleration?
Question 23 options:
[removed]
1)
0.694
[removed]
2)
0.833
[removed]
3)
1.20
[removed]
4)
1.44
[removed]
5)
6.0
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Question 24 (1 point)
Question 24 Unsaved
A stone is thrown from the top of a building with an initial velocity of 20 m/s downward. The top of the building is 60 m above the ground. How much time elapses between the instant of release and the instant of impact with the ground?
Question 24 options:
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1)
2.0 s
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2)
6.1 s
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3)
3.5 s
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4)
1.6 s
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5)
1.0 s
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Question 25 (1 point)
Question 25 Unsaved
A particle moving with a constant acceleration has a velocity of 20 cm/s when its position is x = 10 cm. Its position 7.0 s later is x = -30 cm. What is the acceleration of the particle?
Question 25 options:
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1)
-7.3 cm/s2
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2)
-8.9 cm/s2
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3)
-11 cm/s2
[removed]
4)
-15 cm/s2
[removed]
5)
-13 cm/s2
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Question 26 (1 point)
Question 26 Unsaved
A boy on a skate board skates off a horizontal bench at a velocity of 10 m/s. One tenth of a second after he leaves the bench, to two significant figures, the magnitudes of his velocity and acceleration are:
Question 26 options:
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1)
10 m/s; 9.8 m/s2.
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2)
9.0 m/s; 9.8 m/s2.
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3)
9.0 m/s; 9.0 m/s2.
[removed]
4)
1.0 m/s; 9.0 m/s2.
[removed]
5)
1.0 m/s; 9.8 m/s2.
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Question 27 (1 point)
Question 27 Unsaved
Two identical balls are at rest side by side at the bottom of a hill. Some time after ball A is kicked up the hill, ball B is given a kick up the hill. Ball A is headed downhill when it passes ball B headed up the hill. At the instant when ball A passes ball B,
Question 27 options:
[removed]
1)
it has the same position and velocity as ball B.
[removed]
2)
it has the same position and acceleration as ball B.
[removed]
3)
it has the same velocity and acceleration as ball B.
[removed]
4)
it has the same displacement and velocity as ball B.
[removed]
5)
it has the same position, displacement and velocity as ball B.
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Question 28 (1 point)
Question 28 Unsaved
An automobile moving along a straight track changes its velocity from 40 m/s to 80 m/s in a distance of 200 m. What is the (constant) acceleration of the vehicle during this time?
Question 28 options:
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1)
8.0 m/s
[removed]
2)
9.6 m/s
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3)
12 m/s
[removed]
4)
6.9 m/s
[removed]
5)
0.20 m/s
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Question 29 (1 point)
Question 29 Unsaved
A juggler throws two balls to the same height so that one is at the halfway point going up when the other is at the halfway point coming down. At that point:
Question 29 options:
[removed]
1)
Their velocities and accelerations are equal.
[removed]
2)
Their velocities are equal but their accelerations are equal and opposite.
[removed]
3)
Their accelerations are equal but their velocities are equal and opposite.
[removed]
4)
Their velocities and accelerations are both equal and opposite.
[removed]
5)
Their velocities are equal to their accelerations.
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Question 30 (1 point)
Question 30 Unsaved
An electron, starting from rest and moving with a constant acceleration, travels 2.0 cm in 5.0 ms. What is the magnitude of this acceleration?
Question 30 options:
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1)
2.5 km/s2
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2)
0.80 km/s2
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3)
1.6 km/s2
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4)
1.3 km/s2
[removed]
5)
3.2 km/s2
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Question 31 (1 point)
Question 31 Unsaved
The position of a particle as it moves along the x axis is given by x = 15e-2t m, where t is in s. What is the acceleration of the particle at t = 1 s?
Question 31 options:
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1)
22 m/s
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2)
60 m/s
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3)
8.1 m/s
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4)
15 m/s
[removed]
5)
35 m/s
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Question 32 (1 point)
Question 32 Unsaved
An object is thrown vertically upward such that it has a speed of 25 m/s when it reaches two thirds of its maximum height above the launch point. Determine this maximum height.
Question 32 options:
[removed]
1)
64 m
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2)
48 m
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3)
32 m
[removed]
4)
96 m
[removed]
5)
75 m
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The velocity of a particle moving along the x axis is given for t > 0 by vx = (32.0t – 2.00t3) m/s, where t is in s. What is the acceleration of the particle when (after t = 0) it achieves its maximum displacement in the positive x direction?

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The velocity of a particle moving along the x axis is given for t > 0 by vx = (32.0t – 2.00t3) m/s, where t is in s. What is the acceleration of the particle when (after t = 0) it achieves its maximum displacement in the positive x direction?
Question 11 options:
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1)
-64.0 m/s2
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2)
zero
[removed]
3)
128 m/s2
[removed]
4)
32.0 m/s2
[removed]
5)
-32.0 m/s2
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Question 12 (1 point)
Question 12 Unsaved
An object moving on the x axis with a constant acceleration increases its x coordinate by 80 m in a time of 5.0 s and has a velocity of +20 m/s at the end of this time. Determine the acceleration of the object during this motion.
Question 12 options:
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1)
-1.6 m/s2
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2)
+6.4 m/s2
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3)
+1.6 m/s2
[removed]
4)
-2.0 m/s2
[removed]
5)
-6.4 m/s2
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Question 13 (1 point)
Question 13 Unsaved
A particle starts from rest at xi = 0 and moves for 10 s with an acceleration of +2.0 cm/s2. For the next 20 s, the acceleration of the particle is -1.0 cm/s2. What is the position of the particle at the end of this motion?
Question 13 options:
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1)
zero
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2)
+3.0 m
[removed]
3)
-1.0 m
[removed]
4)
+2.0 m
[removed]
5)
-3.0 m
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Question 14 (1 point)
Question 14 Unsaved
An automobile manufacturer claims that its product will, starting from rest, travel 0.40 km in 9.0 s. What is the magnitude of the constant acceleration required to do this?
Question 14 options:
[removed]
1)
9.9 m/s2
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2)
8.9 m/s2
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3)
6.6 m/s2
[removed]
4)
5.6 m/s2
[removed]
5)
4.6 m/s2
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Question 15 (1 point)
Question 15 Unsaved
A proton moving along the x axis has an initial velocity of 4.0 ´ 106 m/s and a constant acceleration of 6.0 ´ 1012 m/s2. What is the velocity of the proton after it has traveled a distance of 80 cm?
Question 15 options:
[removed]
1)
5.1 ´ 106 m/s
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2)
6.3 ´ 106 m/s
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3)
4.8 ´ 106 m/s
[removed]
4)
3.9 ´ 106 m/s
[removed]
5)
2.9 ´ 106 m/s
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Question 16 (1 point)
Question 16 Unsaved
The position of a particle moving along the x axis is given by x = 6.0t2 – 1.0t3, where x is in meters and t in seconds. What is the position of the particle when it achieves its maximum speed in the positive x direction?
Question 16 options:
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1)
24 m
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2)
12 m
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3)
32 m
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4)
16 m
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5)
2.0 m
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Question 17 (1 point)
Question 17 Unsaved
The area under a graph of vx vs t from t = ti to t = tf represents
Question 17 options:
[removed]
1)
xi.
[removed]
2)
xf.
[removed]
3)
xf – xi.
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4)
equation(xi + xf).
[removed]
5)
xi + xf.
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Question 18 (1 point)
Question 18 Unsaved
Two children start at one end of a street, the origin, run to the other end, then head back. On the way back Joan is ahead of Mike. Which statement is correct about the distances run and the displacements from the origin?
Question 18 options:
[removed]
1)
Joan has run a greater distance and her displacement is greater than Mike’s.
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2)
Mike has run a greater distance and his displacement is greater than Joan’s.
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3)
Joan has run a greater distance, but her displacement is less than Mike’s.
[removed]
4)
Mike has run a greater distance, but his displacement is less than Joan’s.
[removed]
5)
Mike has run a shorter distance, and his displacement is less than Joan’s.
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Question 19 (1 point)
Question 19 Unsaved
A car travels north at 30 m/s for one half hour. It then travels south at 40 m/s for 15 minutes. The total distance the car has traveled and its displacement are:
Question 19 options:
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1)
18 km; 18 km S.
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2)
36 km; 36 km S.
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3)
36 km; 36 km N.
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4)
90 km; 18 km N.
[removed]
5)
90 km; 36 km N.
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Question 20 (1 point)
Question 20 Unsaved
The area under a graph of ax vs t from t = ti to t = tf represents
Question 20 options:
[removed]
1)
xf – xi.
[removed]
2)
vf – vi.
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3)
xavg.
[removed]
4)
vavg.
[removed]
5)
aavg.
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Question 21 (1 point)
Question 21 Unsaved
To help Kim practice for the Special Olympics, Sally runs beside him for half the required distance. She runs the remaining distance at her regular speed and arrives 90 seconds ahead of Kim. What is the ratio of Sally’s regular speed to Kim’s speed? Use tKim for Kim’s total time.
Question 21 options:
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1)
equation
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equation
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equation
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4)
equation
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5)
equation
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Q1: Because Earth's rotation is gradually slowing, the length of each day increases: The day at the end of 1.0 century is 1.0 ms longer than the day at the start of the century. In 91 centuries, what is the total of the daily increases in time (that is, the sum of the gain on the first day, the gain on the second day, etc.)?

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Q1: Because Earth’s rotation is gradually slowing, the length of each day increases: The day at the end of 1.0 century is 1.0 ms longer than the day at the start of the century. In 91 centuries, what is the total of the daily increases in time (that is, the sum of the gain on the first day, the gain on the second day, etc.)?
Q2: Gold, which has a density of 19.32 g/cm3, is the most ductile metal and can be pressed into a thin leaf or drawn out into a long fiber. (a) If a sample of gold with a mass of 3.261 g, is pressed into a leaf of 4.019 μm thickness, what is the area of the leaf? (b) If, instead, the gold is drawn out into a cylindrical fiber of radius 2.400 μm, what is the length of the fiber?
Q3: Grains of fine California beach sand are approximately spheres with an average radius of 50 μm and are made of silicon dioxide, which has a density of 2.8 × 103kg/m3. What mass of sand grains would have a total surface area (the total area of all the individual spheres) equal to the surface area of a cube 1.1 m on an edge?
Q4 :One cubic centimeter of a cumulus contains 330 water drops, which have a typical radius of 10 μm. (a) How many cubic meters of water are in a cylindrical cumulus cloud of height 3.2 km and radius 0.9 km? (b) How many 1-liter pop bottles would that water fill? (c) Water has a density of 1000 kg/m3. How much mass does the water in the cloud have?
Q5: You are to fix dinners for 400 people at a convention of Mexican food fans. Your recipe calls for 3 peppers per serving (one serving per person). However, you have only habanero peppers on hand. The spiciness of peppers is measured in terms of the scoville heat unit (SHU). On average, one pepper has a spiciness of 4000 SHU and one habanero pepper has a spiciness of 300000 SHU. To get the desired spiciness, how many habanero peppers should you substitute for the peppers in the recipe for the 400 dinners?
Q6: From t = 0 to t = 4.07 min, a man stands still, and from t = 4.07 min to t = 8.14 min, he walks briskly in a straight line at a constant speed of 2.47 m/s. What are(a) his average velocity vavg and (b) his average acceleration aavg in the time interval 1.00 min to 5.07 min? What are (c) vavg and (d) aavg in the time interval2.00 min to 6.07 min?
Q7: A ball of moist clay falls 19.2 m to the ground. It is in contact with the ground for 22.0 ms before stopping. (a) What is the average acceleration of the ball during the time it is in contact with the ground? (Treat the ball as a particle.) (b) Is the average acceleration up or down?
Q8: The Zero Gravity Research Facility at the NASA Glenn Reseach Center includes a 138 m drop tower. This is an evacuated vertical tower through which, among other possibilities, a 1 m diameter sphere containing an experimental package can be dropped. (a) How long is the sphere in free fall? (b) What is its speed just as it reaches a catching device at the bottom of the tower? (c) When caught, the sphere experiences an average deceleration of 35.0g as its speed is reduced to zero. Through what distance does it travel during the deceleration?