Physics - Electrostatics

Denise and Elijah are discussing why a balloon sticks to a wall after being rubbed on their hair. Denise explains that it's because of a property of matter that causes it to experience a force when placed in an electromagnetic field. What is this property called?

• a property of matter that causes it to experience a force when placed in an electromagnetic field

• the amount of money billed for a service

• a formal accusation of a crime

• a responsibility or duty

Answer explanation

The correct choice defines 'charge' in physics as a property of matter that interacts with electromagnetic fields, distinguishing it from other meanings like financial charges or responsibilities.

Johanna and Sam are experimenting with balloons. When Johanna rubs a balloon on her hair, it sticks to the wall. What is the force that causes the balloon to stick to the wall?

• A force that occurs due to electric charges

• A force that occurs due to magnetic fields

• A force that occurs due to gravitational attraction

• A force that occurs due to nuclear reactions

Answer explanation

An electrical force arises from the interaction between electric charges. Unlike magnetic forces, gravitational forces, or nuclear forces, it specifically pertains to charged particles, making the first choice correct.

Emilia and Dylan are playing with a balloon. When Emilia rubs the balloon on her hair, the balloon becomes electrically polarized. This means:

• it has an equal number of positive and negative charges distributed uniformly.

• its positive and negative charges are separated, creating a dipole.

• it has more positive charges than negative charges.

• it has more negative charges than positive charges.

Answer explanation

An object is electrically polarized when its positive and negative charges are separated, creating a dipole. This separation leads to an uneven distribution of charge, distinguishing it from a neutral state.

During a science experiment, Dee and Noa are observing the behavior of charges. They notice that some charges remain fixed in place. What type of charges are Dee and Noa studying?

• Moving charges

• Stationary charges

• Both moving and stationary charges

• None of the above

Answer explanation

Electrostatics focuses on stationary charges, which are charges at rest. It does not involve moving charges, which are studied in electrodynamics. Therefore, the correct answer is stationary charges.

Riley and Emilia are setting up a new home theater system. They want to ensure that their electronic devices are safe from electrical faults. What is grounding in the context of electricity?

• A method to increase voltage

• A safety measure to prevent electric shock

• A way to store electrical energy

• A technique to enhance current flow

Answer explanation

Grounding is a safety measure that directs excess electricity into the ground, preventing electric shock and protecting both people and equipment from electrical faults.

Shanoire' and Elijah are sitting on a metal bench in the park. Describe the process of conduction as they feel the heat from the sun warming the bench.

• Conduction is the transfer of heat through a fluid medium.

• Conduction is the transfer of heat through electromagnetic waves.

• Conduction is the transfer of heat through direct contact of particles.

• Conduction is the transfer of heat through a vacuum.

Answer explanation

Conduction occurs when heat is transferred through direct contact of particles in a material. This process allows energy to move from the hotter region to the cooler region, making the correct choice the one that describes this direct contact.

Nate and Jaydon are working on a science project. They need to choose a material for their circuit that allows the flow of electric charge. Which material should they choose?

• a material that allows the flow of electric charge

• a device that stores electrical energy

• a material that resists the flow of electric charge

• a device that converts electrical energy into mechanical energy

Answer explanation

A conductor is defined as a material that allows the flow of electric charge, making it essential for electrical circuits. The other options describe different components or properties unrelated to conductors.

Jaydon and Riley are experimenting with charged particles in their physics class. They observe that around a charged particle, there is:

• a region where a force would be exerted on other charges.

• the flow of electric charge.

• the potential difference between two points.

• the resistance to the flow of electric current.

Answer explanation

An electric field is indeed defined as a region around a charged particle where it exerts a force on other charges. This distinguishes it from concepts like electric charge flow or potential difference.

Sam and Gabby are conducting a science experiment in their classroom. They use an electroscope to:

• measure temperature

• detect electric charge

• measure mass

• detect sound

Answer explanation

An electroscope is a device used to detect electric charge. It shows whether an object is charged by the movement of its leaves, making 'detect electric charge' the correct choice.

Jack and Emilia are observing different types of birds in their backyard. They notice that all the birds they see have wings and can fly. The process they are using to conclude that all birds have wings and can fly involves:

• forming a generalization based on specific observations

• deducing specific instances from a general principle

• testing a hypothesis through experimentation

• applying a known rule to new situations

Answer explanation

The process of induction is about forming a generalization based on specific observations. This means drawing broader conclusions from particular instances, which is the essence of inductive reasoning.