Electric and magnetic force on a charged particle

Multiple Choice

Which of the following best describes the significance of studying electric and magnetic forces on particles?

• It helps us understand how charged particles behave in different environments, which is crucial for technology and scientific research.

• It is only important for understanding magnets.

• It has no real-world applications.

• It is mainly about electricity in homes.

Multiple Choice

Which law states that the acceleration of an object is proportional to the net force and inversely proportional to the mass of the object being accelerated?

• Newton's first law

• Newton's second law

• Newton's third law

• Law of conservation of mass

Open Ended

Describe the main steps and purpose of J.J. Thomson's cathode ray tube experiment.

Multiple Choice

What equation did Thomson use to determine the charge-to-mass ratio of an electron, and what value did he obtain for q/m?

• q/m = v/Br; -1.759 × 10^11 C/kg

• q/m = F/m; -1.602 × 10^-19 C/kg

• q/m = E/B; 9.11 × 10^-31 C/kg

• q/m = v/r; 1.759 × 10^11 C/kg

Fill in the Blank

An electron with a mass of 9.11×10^-31 kg moves through a magnetic field of 6.3×10^-2 T at a speed of 3.0×10^5 m/s. What is the radius of its circular path?

Open Ended

Explain how a mass spectrometer can be used to determine the relative abundance of isotopes in a sample.

Multiple Select

Which of the following statements about isotopes and mass spectrometers are correct?

• Isotopes have the same chemical properties but different masses.

• A mass spectrometer measures the charge-to-mass ratio of positive ions.

• Isotopes have different chemical properties but the same mass.

• A mass spectrometer measures the mass of electrons.

Multiple Choice

Which component in a mass spectrometer is responsible for separating ions based on their mass-to-charge ratio?

• Vacuum chamber

• Magnet

• Gas entry to ion source

• Electronic detector plate

Multiple Select

Which of the following are applications of mass spectrometers?

• Identifying trace elements

• Analyzing the atmospheres and soils of other planets

• Measuring the speed of light

• Determining the boiling point of substances

Fill in the Blank

The charge-to-mass ratio of an ion in a mass spectrometer is given by the formula q/m = ___ .

Open Ended

Explain how the radius of an ion's path in a mass spectrometer is related to its mass and what information this provides about the ion.

Open Ended

Describe the steps involved in determining the radius of an ion's path in a mass spectrometer, using the provided example of doubly ionized neon atoms.

Multiple Choice

In the example problem, what is the value of the magnetic field (B) used to determine the radius of the ion path?

• 0.025 T

• 30.0 V

• 3.3×10^-26 kg

• 1.602×10^-19 C

Open Ended

What is one concept about electric and magnetic forces on particles that you would like to learn more about or found most interesting in this lesson?

Open Ended

How does a mass spectrometer work?

Multiple Choice

Assuming the field and voltage are kept constant, which of the following particles would have the smallest radius of deflection in a mass spectrometer?

• carbon-12, singly ionized (+1)

• carbon-12, doubly ionized (+2)

• carbon-13, singly ionized (+1)

• carbon-13, doubly ionized (+2)