BELLWORK I 2013-2014
FIRST NINE WEEKS
1. How many milliwatts are there in a kilowatt?
A. 100
B. 1,000
C. 1,000,000
D.1,000,000,000
2. A student is trying to decide what subject to study. The student is most interested in the way that molecules of
living things interact. What should the student study?
F. botany
H. geophysics
G. biology
I. biochemistry
3. An astronomer is measuring the distance between a comet and the sun. What units of measurement should the
astronomers use?
A. miles
C. kilometers
B. centimeters
D. micrograms
4. The universal gravitation equation describes how the gravitational attraction between two masses is inversely
proportional to the distance between them squared. What is the universal gravitation equation?
F. a hypothesis
H. a scientific theory
G. a scientific law
I. an experimental result
5. Density equals mass divided by volume. If a chemist is calculating the density of a substance with a known mass
of 23.523 g and a known volume of 17.5 L, how many significant figures will the result have?
AIR MAY BE HEAVIER THAN YOU THINK
In 1642, the Italian scientists Rafael Magiotti and Gasparo Berti attempted to produce a vacuum. They
filled a long tube with water and plugged both ends. Then, they placed the tube upright into a basin of water and
opened the bottom end of the tube. Only a portion of the water in the tube flowed out, and the water still inside the
tube stayed at the level of 10.4 m. Air could not have filled the empty space in the tube because no air had been in
contact with that space. This result seemed to suggest that a vacuum existed in the space above the water. Magiotti
and Berti theorized that the attractive power of that vacuum caused some water to stay in the tube. Evangelista
Torricelli had a different opinion. He hypothesized that air must have weight and that the weight of the air pressing
down on thewater in the basin kept all of the water in the tube from draining out. He performed the same experiment
using mercury, which is 14 times as heavy as water. Mercury stopped flowing out of the tube when the level in the
tube reached a height 14 times lower than the height at which water stopped. Thus, Torricelli’s idea seemed to be
confirmed.
6. A demographics researcher needs a graph comparing the populations of the 10 largest cities in the world. What
would be the best type of graph to use?
7. What was the initial hypothesis of Magiotti and Berti?
A. A long tube filled with water, with both ends plugged, was placed in a basin of water.
B. The weight of air on the basin kept all of the water from flowing out of the tube.
C. The attractive force of the vacuum drew the water up the tube.
D. A vacuum can exist.
8. One of the graphs shows the percentage of the total mass of each of four compounds in a mixture. If there is more
water than any other compound in the mixture, what is the percentage of water in the mixture?
F. 100%
H. 48%
G. 83%
I. 25%
9. One of the graphs shows the results of a fertilization experiment in which four types of fertilizers were applied to
groups of three kinds of plants. The plants’ average height increase was measured. Was there a single fertilizer that
worked best on every plant? How do you know?
The graphic below displays the projected world population in the year 2012, along with the average number of cells
in the human body. Use this graphic to answer question 10.
In the year 2012, how many human cells will there be in the world?
A. 7.0 × 107
C. 1.43 × 107
B. 7.0 × 1022
D. 1.43 × 1022