10.5 Gravitational and Electromagnetic Forces

• Gravitational force is described by Newton's law of universal gravitation
• Electromagnetic force encompasses both electric force and magnetic
• Match the aspect of force with its description:

  Origin of gravitational force ↔️ Mass

  Origin of electromagnetic force ↔️ Electric charge

  Nature of gravitational force ↔️ Always attractive

  Nature of electromagnetic force ↔️ Attractive or repulsive
• Newton's law of universal gravitation states that the force between two objects is proportional to their masses
• What is the relationship between gravitational force and distance according to Newton's law?

  Inversely proportional to the square
• In Coulomb's Law, r represents the distance between the charges.
• The gravitational force is always attractive in nature.
• Electromagnetic force encompasses both electric force and magnetic force.
• What is the origin of gravitational force?

  Mass
• What is the relationship between gravitational force and distance in Newton's Law of Universal Gravitation?

  Inversely proportional to the square
• What does Coulomb's Law describe?

  Force between two point charges
• Coulomb's Law deals with charges, while Newton's Law of Gravitation deals with masses.


  True
• What type of forces pull objects together?

  Attractive forces
• Gravitational force is always attractive because mass is always positive.

  True
• An electric field radiates outward from positive charges.


  True
• Match the type of field with its defining characteristic:

  Gravitational Field ↔️ Always attractive

  Electric Field ↔️ Can be attractive or repulsive
• What is the gravitational force defined as?

  The attractive force between masses
• Gravitational force depends on the distance between objects.


  True
• The origin of gravitational force is mass
• What determines whether electromagnetic force is attractive or repulsive?

  Charge polarities
• What is the origin of gravitational force?

  Mass
• What are the charges denoted by in Coulomb's Law?

  $q_{1}$ and $q_{2}$
• What type of objects are considered in Coulomb's Law?

  Charges
• Gravitational force is proportional to the square of the distance between objects.

  False
• Match the force type with its origin:

  Gravitational Force ↔️ Mass

  Electromagnetic Force ↔️ Electric charge
• Electromagnetic force is much stronger than gravitational force.
• The gravitational constant $G$ is approximately 8.9875 × 10^9 N⋅m^2/C^2.


  False
• What is the relationship between electric force and distance in Coulomb's Law?

  Inversely proportional to the square
• In electromagnetic force, like charges repel each other.
• In electromagnetic force, what happens between like charges?

  They repel
• What is the formula for the strength of a gravitational field?

  g = \frac{GM}{r^2}</latex>
• What is the direction of a gravitational field?

  Towards the mass
• Gravitational potential energy decreases as the distance between objects increases
• What is the nature of gravitational force?

  Always attractive
• Electromagnetic force is stronger than gravitational force.


  True
• Two planets have masses $m_{1} =$$5 × 10^{24} kg$ and $m_{2} =$$8 × 10^{24} kg$, separated by a distance of $r =$$2 × 10^{11} m$. Calculate the gravitational force between them.


  $6.674 × 10^{16} N$
• In Coulomb's Law, the objects are charges, whereas in Newton's Law, they are masses.
• In gravitational force, mass is always positive, so gravity is always attractive.
• What is a gravitational field?

  Region around a mass
• An electric field radiates outward from positive charges and converges inward towards negative charges.

  True