Acceleration Due to Gravity

Definition

Acceleration due to gravity, often denoted as 'g', is the acceleration experienced by an object due to the Earth's gravitational pull. It is a fundamental concept in the study of mechanics and plays a crucial role in understanding the motion of objects near the Earth's surface.

5 Must Know Facts For Your Next Test

1. The value of acceleration due to gravity, 'g', is approximately 9.8 meters per second squared (m/s^2) near the Earth's surface.
2. Acceleration due to gravity is a vector quantity, meaning it has both magnitude and direction, and is directed towards the center of the Earth.
3. The acceleration due to gravity is independent of an object's mass, as demonstrated by Galileo's experiments with falling objects.
4. Newton's Universal Law of Gravitation describes the gravitational force between any two objects with mass, and is used to calculate the acceleration due to gravity.
5. The acceleration due to gravity can be used to calculate the weight of an object, which is the force exerted by gravity on the object.

Review Questions

• Explain how Newton's Universal Law of Gravitation relates to the acceleration due to gravity.
  • According to Newton's Universal Law of Gravitation, the gravitational force between two objects is proportional to their masses and inversely proportional to the square of the distance between them. This law can be used to calculate the acceleration due to gravity experienced by an object near the Earth's surface, as the Earth's mass and the distance to the object's location are known. The acceleration due to gravity is a direct consequence of the gravitational force acting on the object, as described by Newton's Second Law of Motion.
• Describe the relationship between acceleration due to gravity and the motion of objects in free fall.
  • When an object is in free fall, it is only subject to the force of gravity and experiences a constant acceleration towards the Earth's surface. This acceleration, known as the acceleration due to gravity, is independent of the object's mass. The motion of an object in free fall can be described using the kinematic equations, which relate the object's position, velocity, and acceleration over time. The acceleration due to gravity is a critical parameter in these equations, as it determines the rate at which the object's velocity increases and its position changes during free fall.
• Analyze how the acceleration due to gravity can be used to calculate the weight of an object.
  • The weight of an object is the force exerted on the object by the Earth's gravity. This force can be calculated by multiplying the object's mass by the acceleration due to gravity. The formula for an object's weight is $W = mg$, where $W$ is the weight, $m$ is the mass of the object, and $g$ is the acceleration due to gravity. By knowing the value of the acceleration due to gravity, which is approximately 9.8 m/s^2 near the Earth's surface, and the mass of the object, one can determine the object's weight. This relationship between acceleration due to gravity, mass, and weight is a fundamental concept in the study of mechanics and is essential for understanding the motion and behavior of objects in the presence of gravity.

Related terms

Gravitational Force:

The attractive force between two objects with mass, as described by Newton's Universal Law of Gravitation.

Free Fall: The motion of an object under the sole influence of gravity, with no other external forces acting upon it.

Newton's Second Law of Motion: The relationship between an object's acceleration, the net force acting on it, and its mass, expressed as $F = ma$.