Physics Chapter on Free Fall

Study Notes

Initial Conditions

A steel ball is dropped from a height of 100 meters.
The initial velocity is zero (0 m/s) as it's dropped, not thrown.
After one second, the velocity of the ball is 10 m/s.

Acceleration Due to Gravity

The ball accelerates downwards due to gravity.
The acceleration due to gravity is approximately 9.8 m/s².
This means the velocity of the ball increases by 9.8 m/s every second.

Velocity Calculation after One Second

The velocity after one second (10 m/s) can be calculated using the equation: v = u + at, where:
- v = final velocity
- u = initial velocity
- a = acceleration
- t = time
If u=0 m/s, a = 9.8 m/s², and t = 1 s, then v = 0 + (9.8 * 1) = 9.8 m/s
The given value of 10 m/s is likely an approximation.

Velocity Calculation after Two Seconds

To find the velocity after two seconds (t = 2 seconds), use the same formula:
- v = u + at
  - Where:
    - u = initial velocity (0 m/s)
    - a = acceleration due to gravity (approximately 9.8 m/s²)
    - t = time (2 seconds)
v = 0 + (9.8 * 2) = 19.6 m/s
Therefore, the velocity of the ball after two seconds will be approximately 19.6 m/s.

Important Considerations

Air resistance is ignored in this calculation. In reality, air resistance would slightly reduce the acceleration and final velocity.
The value of acceleration due to gravity (9.8 m/s²) is an approximation; it can vary slightly depending on location. This is important for more precise calculations.
The given velocity after one second (10 m/s) might be an approximation rounded from the more accurate value (9.8 m/s).

Description

This quiz covers the principles of free fall, including initial conditions and the equations used to calculate velocity under the influence of gravity. It focuses on the effects of gravity on a dropped steel ball and provides fundamental insights into motion involving acceleration. Test your understanding of these concepts.