A block of maple wood with a volume of 405 cubic centimeters and a density of 0.67 g/cm3 is sawed in half. The density of the two smaller blocks is now —
A one-fourth the original density
B one-half the original density
C the same as the original density
D two times the original density
the same as the original density
Which of the following choices correctly describes all of the energy transformations that occur in an electric pencil sharpener?
A Electrical energy is converted to mechanical energy.
B Chemical energy is converted to electrical energy, producing sound.
C Electrical energy is converted to mechanical, thermal, and sound energy.
D Mechanical energy is converted to electrical and sound energy.
C Electrical energy is converted to mechanical, thermal, and sound energy.
The picture shows an inclined plane that was used to move a heavy box. Which of these does the inclined plane change?
A The mass of the box being moved
B The amount of force required to move the box
C The amount of work required to move the box
D The amount of energy required to move the box
B The amount of force required to move the box
Scientists want to study conditions on Europa, a natural satellite of Jupiter. This object is 588 million kilometers (356 million miles) away from Earth. Which type of equipment would be best for scientists to send to study conditions on Europa?
A the space shuttle
B a commercial satellite
C a probe with instruments
D the Voyager II spacecraft
C a probe with instruments
The solid part of Earth’s surface is called the –
A core
B lithosphere
C mantle
D cryosphere
B lithosphere
What is the best evidence that new substances form when a birthday candle burns?
A Color of candle wick changes
B Room gets hotter
C Candle flame grows larger
D Wax melts
Color of candle wick changes
A flowing stream contains water at 18ºC. Cans of soft drinks at 28ºC are lowered into the stream. Which of the following will most likely occur?
A The soft drink cans will absorb cold energy from the stream’s water.
B The cans will cool until their temperature is the same as the stream’s.
C The temperature of the soft drinks will not change since the cans are sealed.
B The cans will cool until their temperature is the same as the stream’s.
Newton’s 3rd law states that for every action force there is an equal and opposite reaction force. A student pushes against a wall with 20 N of force and the wall does not move. In this situation, the wall exerts –
A more than 20 N of force
B less than 20 N of force
C 20 N of force
D 0 N of force
C 20 N of force
People go to the International Space Station and live there for months at a time. All of the following are risks of living in space, EXCEPT –
A dangers in the surrounding environment
B high radiation levels due to no atmosphere
C effects on the body because of microgravity
D eating food and exercising
D eating food and exercising
A chemical property of a mineral is evident if the mineral –
A breaks easily when struck with a hammer
B bubbles when acid is placed on it
C is easily scratched by a fingernail
D reflects light from its surface
B bubbles when acid is placed on it
An unidentified element has many of the same physical and chemical properties as magnesium and strontium but has less mass than either of these elements. What is the most likely identity of this element?
A Sodium
B Rubidium
C Beryllium
D Calcium
Beryllium
Which is the best action to help protect water resources in Texas?
A Dispose of pet waste in a stream.
B Rinse spilled gasoline with a hose.
C Organize a river cleanup program.
D Put hazardous waste in with house trash.
C Organize a river cleanup program.
Compare the two situations shown below. In Situation 2, the box is pushed up the ramp instead of lifted straight up, as in Situation 1.
How does using this simple machine, called an inclined plane, make the work easier?
A decreases the amount of work needed to lift the box
B decreases the distance over which the force is applied
C decreases the amount of motion needed to lift the box
D decreases the amount of effort needed to lift the box
D decreases the amount of effort needed to lift the box
Fusion is a form of nuclear reaction resulting in an enormous release of heat energy. Where does the fusion of hydrogen to helium typically occur?
A In the Sun and other stars
B In the ionosphere and thermosphere of planets
C In Earth’s outer core of molten iron
D In a comet’s tail of ionized gases
A In the Sun and other stars
Which of these features makes Earth unique among planets?
A It is the only solid round planet.
B It is the only planet with its own moon that orbits it.
C It is the only planet where volcanic activity has ever occurred.
D It is the only planet that has 21% oxygen in the atmosphere.
D It is the only planet that has 21% oxygen in the atmosphere.
A student measures the masses of two objects using a balance before placing them in graduated cylinders. One is a metal rod, the other is a ring. Using the image below, which one has a larger volume?
A The volume of the objects is the same.
B The volume of the metal rod.
C The volume of the ring.
D There is not enough information to decide.
The metal rod has a larger volume.
Which of these BEST shows a change from potential to kinetic energy?
A Water falling from a cliff making a waterfall
B Electricity making a bulb light up
C Transfer of heat through electromagnetic waves
D A rubber band being stretched
A Water falling from a cliff making a waterfall
The diagram below shows a box and the direction of the action force applied to the box.
Which of the following shows the direction of the reaction force?
A left
B right
C up
D down
A left
An object will continue moving in a straight line unless it is acted on by an unbalanced force. Which of the following best explains Earth’s motion?
A There is no unbalanced force acting on Earth because space is empty and nothing touches Earth.
B Earth moves in an elliptical orbit around the sun because the gravitational force of the sun attracts Earth.
C The sun moves in an elliptical orbit around Earth, and the sun’s gravity pulls Earth along.
D The gravitational force pulling Earth toward the sun is equal and opposite to the force pulling the sun toward Earth, so there is no unbalanced force acting on Earth.
B Earth moves in an elliptical orbit around the sun because the gravitational force of the sun attracts Earth.
The thick black lines on the map show the locations of mid-ocean ridges where two plate boundaries are moving away from each other.
Which geologic feature is most likely to form at a mid-ocean ridge?
A Peninsula
B Volcano
C Delta
D Plateau
B Volcano
What is the most important consideration when selecting material to make jewelry, horse shoes or the body of a car?
A malleability
B sensitivity
C flammability
D conductivity
A. malleability
A student drew the diagram below to show the movement of water through a hydroelectric dam.
The student used the diagram to describe changes in the potential and kinetic energy of the water. At which location is the potential energy of the water the greatest?
A Location W
B Location X
C Location Y
D Location Z
A Location W
Jason and his friends are playing with his remote control car. If the remote control car takes 20 seconds to cover a distance of 100 meters, what is its average speed?
A 2.0 m/s
B 5.0 m/s
C 50.0 m/s
D 200.0 m/s
B 5.0 m/s
What force causes Venus to travel along a curved path instead of moving in a straight line as indicated by the dashed line in the diagram?
A Electromagnetic attraction between the sun and Venus
B Gravitational attraction between the sun and Venus
C Electromagnetic attraction between Mercury and Venus
D Gravitational attraction between Mercury and Venus
B Gravitational attraction between the sun and Venus
Many scientists believe that crustal plate movement occurs because of convection cells contained in Earth’s –
A crust
B hydrosphere
C mantle
D inner core
C mantle