Physics Chapter on Displacement

Questions and Answers

Which of the following statements accurately describes displacement?

Displacement is always equal to the distance traveled.

Displacement can never be negative.

Displacement measures the total distance traveled regardless of direction.

Displacement is the straight-line distance between the initial and final positions. (correct)

How is average velocity calculated when given displacement and time?

Average velocity = speed multiplied by distance.

Average velocity = distance multiplied by time.

Average velocity = time divided by displacement.

Average velocity = displacement divided by time. (correct)

What distinguishes velocity from speed?

Velocity measures the distance traveled over time, while speed is constant.

Velocity is a scalar quantity, while speed is a vector quantity.

Velocity includes direction, while speed does not. (correct)

Velocity can only be calculated for linear motion, unlike speed.

In the context of Maria's walk, what is her displacement from her initial position at home to the park?

50 meters east. Signup and view all the answers

If an airplane passenger moves -4 m horizontally in 5 seconds, what is their average velocity?

-0.8 m/s. Signup and view all the answers

What is the key distinction between distance and displacement?

Distance is a scalar quantity measuring total path length, whereas displacement is a vector quantity measuring shortest path. Signup and view all the answers

Which of the following best defines velocity?

The rate of change of displacement over time. Signup and view all the answers

If a car travels 200 km east in 2 hours, what is its average velocity?

100 km/h east Signup and view all the answers

What characterizes instantaneous acceleration?

It can be defined as the change in velocity over an infinitesimal time interval. Signup and view all the answers

Which statement accurately distinguishes between vector and scalar quantities?

Vector quantities have magnitude and direction, while scalar quantities have only magnitude. Signup and view all the answers

Study Notes

Displacement

Defined as the change in position of an object, represented by the equation: ( x = x_f - x_0 )
( x_f ) is the final position, and ( x_0 ) is the initial position.
Example calculation: If ( x_f = 3.5 , \text{m} ) and ( x_0 = 1.5 , \text{m} ), then displacement ( x = 2.0 , \text{m} ).

Example of Displacement

Maria walks 200 m east (initial position = 0 m) and then 150 m west.
Final position calculation: ( x_f = 0 + 200 , \text{m} - 150 , \text{m} = 50 , \text{m} ) east.
Displacement from her house to the park is ( 50 , \text{m} ).

Speed vs. Velocity

Speed is a scalar quantity, meaning it has magnitude but no direction.
Velocity is a vector quantity that includes both magnitude and direction, usually expressed in units like mph or km/h.

Average Velocity

Calculated as the displacement divided by the time taken: [ v_{ave} = \frac{\Delta x}{\Delta t} ]
( \Delta x ) is the displacement, and ( \Delta t ) is the change in time.

Time

Time measures the interval over which change occurs, with SI unit as seconds (s).
Elapsed time calculation: [ t = t_f - t_0 ]
Example: If the ending time is 6:30 and starting time is 3:00, elapsed time = 3.5 hours.

Practical Example of Time

John starts hiking at 9:30 AM and finishes at 12:45 PM with a 15-minute break.
Total hiking time without the break can be calculated.

Acceleration

Defined as the rate of change of velocity, which includes changes in speed and direction.
Acceleration is a vector quantity.

Deceleration vs. Negative Acceleration

Deceleration occurs when the acceleration acts in the opposite direction of velocity, reducing speed.
Negative acceleration refers to acceleration that opposes the defined positive direction in a coordinate system.

Instantaneous Acceleration

Refers to acceleration at a specific instant in time, similar to calculating instantaneous velocity.

Description

This quiz covers the concept of displacement in physics, including its definition, formula, and a sample calculation. You will learn how to determine the displacement by using the initial and final position of an object.