Relative Motion in Physics

Questions and Answers

What is the distance between two bodies moving towards each other?

The difference of the objects' displacements from a shared origin point

Half of the sum of the objects' displacements from a shared origin point

The sum of the objects' displacements from a shared origin point (correct)

The average of the objects' displacements from a shared origin point

What is the condition for one object to overtake another?

When the two objects have the same velocity

When the two objects have the same acceleration

When the two objects have the same displacement from a certain point (correct)

When the two objects have the same distance from the origin point

What is the acceleration due to gravity near the Earth's surface?

11.0 m/s2

10.2 m/s2

9.8 m/s2 (correct)

9.5 m/s2

What is the step to solve a free fall question?

Identify the equation of motion with one unknown variable Signup and view all the answers

When does an object reach its maximum height in a free fall?

When its speed is zero Signup and view all the answers

What is the condition for one object to fully pass another?

The difference in the displacements of both objects is equal to the total length Signup and view all the answers

What is the force acting on an object when it is free falling?

Gravity only Signup and view all the answers

What should be considered when solving a free fall question?

Always consider the sign difference for vectors pointing up and down Signup and view all the answers

If two objects are moving towards each other, what determines the distance between them?

The sum of their displacements from a shared origin point Signup and view all the answers

An object is trying to catch up to another object that is 50m ahead. If they have the same velocity, how far will the first object need to travel to catch up?

50m Signup and view all the answers

What is the necessary condition for one object to fully pass another?

The difference in their displacements is equal to the total length of both objects Signup and view all the answers

An object is dropped from rest near the Earth's surface. What is its acceleration?

9.8 m/s^2 downwards Signup and view all the answers

What is the velocity of an object at its maximum height in a free fall?

0 m/s Signup and view all the answers

Study Notes

Relative Motion

The distance between two bodies is the sum of their displacements from a common origin point.
When two objects move towards each other, their displacements are calculated from a shared reference point.

Catching Up

An object overtakes another when they have the same displacement from a certain point.
If objects start from the same point, it's easy to determine when they will catch up.
If one object starts ahead of the other, the difference in their initial displacements must be added to the equation.
If objects start at the same point but at different times, the time difference is added to the equation.

Passing

For one object to fully pass another, it must cover a distance equal to the total length of both objects.
The difference in displacements between the two objects must be equal to this distance.

Acceleration Due to Gravity

When an object is in free fall, only gravity acts on it, causing it to accelerate towards the ground at 9.8 m/s² near the Earth's surface.
Steps to solve a free fall problem:
- Identify the equation of motion with only one unknown variable.
- Substitute known values, including acceleration (a = -9.8 m/s²).
- Ensure consistent sign convention for vectors pointing up and down.
- Solve for the unknown variable.
- For maximum height, the object's speed is 0.

Relative Motion

The distance between two bodies is the sum of their displacements from a common origin point.
When two objects move towards each other, their displacements are calculated from a shared reference point.

Catching Up

An object overtakes another when they have the same displacement from a certain point.
If objects start from the same point, it's easy to determine when they will catch up.
If one object starts ahead of the other, the difference in their initial displacements must be added to the equation.
If objects start at the same point but at different times, the time difference is added to the equation.

Passing

For one object to fully pass another, it must cover a distance equal to the total length of both objects.
The difference in displacements between the two objects must be equal to this distance.

Acceleration Due to Gravity

When an object is in free fall, only gravity acts on it, causing it to accelerate towards the ground at 9.8 m/s² near the Earth's surface.
Steps to solve a free fall problem:
- Identify the equation of motion with only one unknown variable.
- Substitute known values, including acceleration (a = -9.8 m/s²).
- Ensure consistent sign convention for vectors pointing up and down.
- Solve for the unknown variable.
- For maximum height, the object's speed is 0.