Questions About Electric Forces - Middle School Physical Science
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Which core material change typically increases an electromagnet’s strength: air core or iron core?
Which core material change typically increases an electromagnet’s strength: air core or iron core?
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Iron core increases strength. Iron concentrates magnetic field lines better than air.
Iron core increases strength. Iron concentrates magnetic field lines better than air.
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What is the dependent variable in a test of magnetic force strength using paper clips?
What is the dependent variable in a test of magnetic force strength using paper clips?
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Number of paper clips lifted (force indicator). Measures force indirectly by counting objects the magnet can lift.
Number of paper clips lifted (force indicator). Measures force indirectly by counting objects the magnet can lift.
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What is the independent variable in a test of magnetic force vs. distance from a magnet?
What is the independent variable in a test of magnetic force vs. distance from a magnet?
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Distance from the magnet. The variable you change to test its effect on magnetic force.
Distance from the magnet. The variable you change to test its effect on magnetic force.
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Which change increases electric force more: doubling $q_1$ or doubling both $q_1$ and $q_2$?
Which change increases electric force more: doubling $q_1$ or doubling both $q_1$ and $q_2$?
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Doubling both $q_1$ and $q_2$. Doubling both charges quadruples the force ($2 imes 2 = 4$).
Doubling both $q_1$ and $q_2$. Doubling both charges quadruples the force ($2 imes 2 = 4$).
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What is the relationship between electric force and charge magnitude in Coulomb’s law?
What is the relationship between electric force and charge magnitude in Coulomb’s law?
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Electric force increases as charge magnitude increases. Force is directly proportional to each charge's magnitude.
Electric force increases as charge magnitude increases. Force is directly proportional to each charge's magnitude.
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Identify the controlled variables when testing how $q_1$ affects electric force between two objects.
Identify the controlled variables when testing how $q_1$ affects electric force between two objects.
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Keep $q_2$ and $r$ constant. Isolates $q_1$'s effect by keeping other factors unchanged.
Keep $q_2$ and $r$ constant. Isolates $q_1$'s effect by keeping other factors unchanged.
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Which factor determines whether the electric force between two charges is attractive or repulsive?
Which factor determines whether the electric force between two charges is attractive or repulsive?
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The signs of the charges. Opposite signs attract; same signs repel.
The signs of the charges. Opposite signs attract; same signs repel.
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Which change would make electric force stronger: doubling $q_1$ or doubling $r$?
Which change would make electric force stronger: doubling $q_1$ or doubling $r$?
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Doubling $q_1$ makes the force stronger. Doubling $r$ weakens force by factor of 4; doubling charge doubles force.
Doubling $q_1$ makes the force stronger. Doubling $r$ weakens force by factor of 4; doubling charge doubles force.
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Which factor must be kept constant when testing how distance affects electric force strength?
Which factor must be kept constant when testing how distance affects electric force strength?
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Charge amounts (and their signs). Must stay the same to isolate distance's effect on force.
Charge amounts (and their signs). Must stay the same to isolate distance's effect on force.
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What is the independent variable in an investigable question about electric force vs. distance?
What is the independent variable in an investigable question about electric force vs. distance?
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Distance between the charges. The variable you change to test its effect on force.
Distance between the charges. The variable you change to test its effect on force.
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Which variable most directly changes an electromagnet’s strength in a simple circuit?
Which variable most directly changes an electromagnet’s strength in a simple circuit?
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Electric current through the coil. Current creates the magnetic field in an electromagnet.
Electric current through the coil. Current creates the magnetic field in an electromagnet.
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What is the dependent variable in an investigable question about electric force vs. distance?
What is the dependent variable in an investigable question about electric force vs. distance?
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Measured electric force strength. The variable you measure to see the effect of distance.
Measured electric force strength. The variable you measure to see the effect of distance.
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Which change should increase electromagnet strength: increasing current or increasing distance to the object?
Which change should increase electromagnet strength: increasing current or increasing distance to the object?
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Increasing current. More current creates stronger magnetic field; distance weakens it.
Increasing current. More current creates stronger magnetic field; distance weakens it.
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Which factor must be kept constant when testing how the number of coil turns affects electromagnet strength?
Which factor must be kept constant when testing how the number of coil turns affects electromagnet strength?
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Current and core material. Isolates coil turns' effect by keeping other factors unchanged.
Current and core material. Isolates coil turns' effect by keeping other factors unchanged.
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Identify the independent variable in this question: “How does coil turn count affect electromagnet strength?”
Identify the independent variable in this question: “How does coil turn count affect electromagnet strength?”
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Number of coil turns. The variable being changed to test its effect on strength.
Number of coil turns. The variable being changed to test its effect on strength.
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What happens to magnetic force between two magnets when the distance between them increases?
What happens to magnetic force between two magnets when the distance between them increases?
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It decreases. Magnetic fields weaken with distance from the source.
It decreases. Magnetic fields weaken with distance from the source.
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What is the SI unit of force used for electric and magnetic forces?
What is the SI unit of force used for electric and magnetic forces?
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Newton (N). Named after Isaac Newton; measures all types of forces.
Newton (N). Named after Isaac Newton; measures all types of forces.
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Choose the investigable question: “Why are magnets special?” or “How does distance change magnet strength?”
Choose the investigable question: “Why are magnets special?” or “How does distance change magnet strength?”
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How does distance change magnet strength. Second option is testable; first is too vague to investigate.
How does distance change magnet strength. Second option is testable; first is too vague to investigate.
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Identify the dependent variable in: “How does current affect an electromagnet’s strength?”
Identify the dependent variable in: “How does current affect an electromagnet’s strength?”
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Electromagnet strength (measured magnetic force). The measured outcome that depends on current changes.
Electromagnet strength (measured magnetic force). The measured outcome that depends on current changes.
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Identify the independent variable in: “How does distance affect the force between two charges?”
Identify the independent variable in: “How does distance affect the force between two charges?”
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Distance between the charges. The variable you change to test its effect on force.
Distance between the charges. The variable you change to test its effect on force.
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What happens to an electromagnet’s strength when an iron core is added to the coil?
What happens to an electromagnet’s strength when an iron core is added to the coil?
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It increases. Iron concentrates and amplifies the magnetic field.
It increases. Iron concentrates and amplifies the magnetic field.
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What happens to an electromagnet’s strength when the number of coil turns increases?
What happens to an electromagnet’s strength when the number of coil turns increases?
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It increases. More turns concentrate the magnetic field lines.
It increases. More turns concentrate the magnetic field lines.
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What happens to an electromagnet’s strength when the current in the coil increases?
What happens to an electromagnet’s strength when the current in the coil increases?
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It increases. More current means stronger magnetic field around the wire.
It increases. More current means stronger magnetic field around the wire.
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What factor about a magnet most directly affects how strong its magnetic force can be?
What factor about a magnet most directly affects how strong its magnetic force can be?
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Magnet strength (magnetization) and size/material. Stronger magnets have more aligned magnetic domains.
Magnet strength (magnetization) and size/material. Stronger magnets have more aligned magnetic domains.
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Which interaction occurs when a north pole faces a south pole of another magnet?
Which interaction occurs when a north pole faces a south pole of another magnet?
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Attraction. Opposite magnetic poles attract each other.
Attraction. Opposite magnetic poles attract each other.
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