Dissolving and Mixtures
Which of the following can be removed from a mixture using a magnet?
a.Cooking oil
b.Iron filings
c.Salt
d.Sand
B. Iron filings
Jack is pulling a rope to the left. Singh is pulling the rope to the right. The rope stayed in the same position. Which reasoning best explains why the rope does not move?
A. The two forces are acting in the same direction.
B. The two forces are equal and balanced each other out.
C. Two forces cannot act on one object at the same time.
D. The force to the left in greater than the forces to the right.
B. The two forces are equal and balanced each other out.
Frank was late for school and dashed through the house and across the living room rug when he reached for the metal doorknob. He felt a little electrical charge in his fingers. What is the most likely reason Frank felt an electrical charge in his fingers?
A. Static electricity
B. Friction
C. Gravity
D. Condensation
A. Static electricity
Clayton tries to build an electric circuit using a battery, a light bulb, a paper clip, and a copper wire. The diagram below shows what he builds. Which statement best explains why the circuit would not conduct electricity?
A. The circuit lacks a power source.
B. The circuit is not a complete loop.
C. The light bulb uses the electric current.
D. The paper clip stops the electric current
B. The circuit is not a complete loop.
Anything an electrical current can pass through easily.
What is conductor?
Which combination of substances from the chart above would dissolve in water?
a.Sand and salt
b.Cooking oil and sugar
c.Sugar and iron filings
d.Sugar and salt
D. sugar and salt
An electrically charged object is similar to a magnet because?
A. Both a magnet and an electrically charged object can use heat to attract and repel objects without touching the objects
B. Both a magnet and an electrically charged object can attract or repel objects without touching the objects
C. Neither a magnet or an electrically charged object can attract or repel objects without touching the objects
D. Neither a magnet nor an electrically charged object can be attracted to another object
B. Both a magnet and an electrically charged object can attract or repel objects without touching the objects
Serena is building an electric circuit for a science project. Which of the following does Serena need for electricity to flow through the circuit?
A. The circuit needs a light bulb.
B. The circuit needs a poor conductor (insulator)
C. The circuit must be open at one end.
D. The circuit must be a complete loop
D. The circuit must be a complete loop
What part of a roller coaster has the most potential energy?
The top
Mr. Jones is looking for seashells hidden in the sand on the beach. How could he quickly separate any seashells from the sand?
a. He could pour the sand through a sieve.
b. He could dissolve the sand in salt water.
c. He could dissolve the sand in fresh water.
d. He could pass a magnet over the surface of the sand.
a. He could pour the sand through a sieve.
While playing with his magnet toy car set, Izzi noticed that when he tried to put the cars facing each other they actually moved in opposite directions. Why did the cars move in opposite directions?
A. This is an example of gravity moving the cars.
B. This is an example of friction moving the cars.
C. This is an example of attraction moving the cars.
D. This is an example of repulsion moving the cars.
D. This is an example of repulsion moving the cars.
Sonia was rubbing a comb with a wool cloth. She used the comb to…
A. classify other objects that were metal by touching the comb to them
B. attract uncharged bits of paper by moving the comb near them
C. explain how a closed circuit works by holding the comb in one hand and the wool cloth in the other.
D. understand the relationship between the mass of the comb and the volume of the wool cloth
B. attract uncharged bits of paper by moving the comb near them
Erica is testing common household objects. She is sorting them into good conductors of electricity and poor conductors of electricity. Which object would be the best conductor of electricity?
A. foam cup
B. metal spoon
C. wooden toy
D. plastic comb
B. metal spoon
Richie made an electrical circuit to make a light bulb light up. Which of the following parts would not conduct electricity?
A. battery
B. lightbulb
C. plastic battery holder
D. copper wire
C. plastic battery holder
Ming wants to dissolve 10 grams of salt in water. Which of the following will make the salt dissolve fastest?
a. Using cold water and stirring the mixture
b. Using hot water without stirring the mixture
c. Using hot water and stirring the mixture
d. Using cold water without stirring the mixture
c. Using hot water and stirring the mixture
An electromagnet is metal that is electrically charged using electricity. Michael discovered that electromagnets are used to pick up old cars and move them from one place to another at the junk yard. He correctly hypothesizes that:
A. A motionless object can attract an uncharged object
B. An electrically charged object can attract an uncharged object
C. A balanced force can move an uncharged object
D. An electrically charged object will not attract an uncharged object
B. An electrically charged object can attract an uncharged object
The plastic coating was stripped off the end of the piece of wire shown below. Why must the plastic be removed before this wire is used in an electric circuit?
A. So the wire can be bent and fit into the circuit
B. To prevent the circuit from becoming overloaded
C. Because the plastic makes the wire too thick to use in a circuit.
D. So that electric current can pass between the copper and other parts of the circuit.
D. So that electric current can pass between the copper and other parts of the circuit.
Rosa spilled some salt on the table. Next she rubbed a balloon on her brother’s head. Then she held the balloon near the salt. The salt moved toward the balloon. What made this happen?
A. The electrical charge on the balloon attracts the salt.
B. The electrical charge on the balloon repels the salt and lifts it up.
C. The magnetism on the balloon attracts the salt.
D. The magnetism on the balloon repels the salt.
A. The electrical charge on the balloon attracts the salt.
How can you separate salt water and sand?
a. magnet and sieve
b. filter and sieve
c. evaporation and magnet
d. evaporation and filter
d. evaporation and filter
Bianca pushes an empty box across a flat surface with little effort. She then fills the box up with books and tries to push it. Which claim describes what will most likely happen?
A. The box will be easier to move because Bianca’s push will have less effect on the heavier box.
B. The box will be easier to move because Bianca’s push will have a greater effect on the heavier box.
C. The box will be harder to move because Bianca’s push will have less effect on the heavier box.
D. The box will be harder to move because Bianca’s push will have a greater effect on the heavier box.
C. The box will be harder to move because Bianca’s push will have less effect on the heavier box.
A student has two balloons each hanging from a string from a table and a wool piece of cloth. She is going to rub one of the balloons with the cloth for 30 seconds. She will then make observations about the two balloons. Which idea is most likely being investigated by the student?
A. She is investigating sound energy with the two balloons.
B. She is investigating air energy with the two balloons.
C. She is investigating static electricity with the two balloons.
D. She is investigating refraction with the two balloons.
C. She is investigating static electricity with the two balloons.
How must the circuit look in order for it to work?
A complete loop or circle (closed circuit)
Gabriel is designing an experiment to see whether sugar or artificial sweetener will attract the greatest number of ants. Which statement best describes why Gabriel should write down his experimental procedure?
A. The exact experiment can be repeated by others and the results compared.
B. The experiment can be changed by others to get different results.
C. The data will help people decide what type of sweetener to use.
D. The data will show people which ants are more common.
A. The exact experiment can be repeated by others and the results compared.