Graphs of Projectile Motion Type 1: Dropping a projectile

1. Understanding Free-Fall Motion

When a projectile is dropped (from rest) from a certain height:
- Initial velocity $(v_i) = 0 m/s.$
- Velocity increases as the object falls downwards.
- Velocity is maximum $(v_f)$ just before hitting the ground.
- Acceleration remains constant at g = 9.8 m/s² downwards.

2. Choosing a Positive Direction

Two approaches:
- Downwards as positive
- $v_i = 0 $$, g = +9.8$ $m/s²$
- Displacement increases in the positive direction
- Upwards as positive
- $v_i = 0, g = -9.8m/s²$
- Displacement decreases (negative values)

3. Graphs of Motion for Dropped Objects

Displacement-Time Graph $(y-t)$

Parabolic curve
Starts at zero and increases faster as the object falls.
Steeper curve = increasing velocity.

Velocity-Time Graph $(v-t)$

Straight line with a positive slope (if down is positive).
Velocity increases uniformly due to constant acceleration.

Acceleration-Time Graph $(a-t)$

Constant horizontal line at -9.8 m/s² (if up is positive).
Constant horizontal line at +9.8 m/s² (if down is positive).

infoNote

4. Worked Example: Ball Dropped from a Building

Scenario:

A ball (0.2 kg) is dropped from a 100 m high building.
Ignore air resistance.
Find:

The velocity just before impact.
The time taken to reach the ground.

Solution:

Step 1: Find Final Velocity $(v_f)$

Using:

$v_f^2 = v_i^2 + 2g\Delta y$

$v_f^2 = 0 + 2(9.8)(100)$

$v_f = :success[44.27 text{ m/s downwards}]$

Step 2: Find Time $(\Delta t)$

Using:

$v_f = v_i + g\Delta t$

$44.27 = 0 + (9.8) \Delta t$

$\Delta t = :success[4.52 text{ s}]$

5. Key Takeaways

Choose a positive direction before solving.
Graphs represent motion clearly:
- Displacement-Time Graph: Parabolic (curved).
- Velocity-Time Graph: Straight line.
- Acceleration-Time Graph: Constant.
Gravitational acceleration is always 9.8 m/s² downwards.

Graphs of Projectile Motion Type 1: Dropping a projectile Simplified Revision Notes for NSC Physical Sciences

Graphs of Projectile Motion Type 1: Dropping a projectile

1. Understanding Free-Fall Motion

2. Choosing a Positive Direction

3. Graphs of Motion for Dropped Objects

Displacement-Time Graph $(y-t)$

Velocity-Time Graph $(v-t)$

Acceleration-Time Graph $(a-t)$

4. Worked Example: Ball Dropped from a Building

Scenario:

Solution:

Step 1: Find Final Velocity $(v_f)$

Step 2: Find Time $(\Delta t)$

5. Key Takeaways

500K+ Students Use These Powerful Tools to Master Graphs of Projectile Motion Type 1: Dropping a projectile For their NSC Exams.

Other Revision Notes related to Graphs of Projectile Motion Type 1: Dropping a projectile you should explore

Graphs of Projectile Motion Type 1: Dropping a projectile Simplified Revision Notes for NSC Physical Sciences

Graphs of Projectile Motion Type 1: Dropping a projectile

1. Understanding Free-Fall Motion

2. Choosing a Positive Direction

3. Graphs of Motion for Dropped Objects

Displacement-Time Graph (y−t)(y-t)(y−t)

Velocity-Time Graph (v−t)(v-t)(v−t)

Acceleration-Time Graph (a−t)(a-t)(a−t)

4. Worked Example: Ball Dropped from a Building

Scenario:

Solution:

Step 1: Find Final Velocity (vf)(v_f)(vf​)

Step 2: Find Time (Δt)(\Delta t)(Δt)

5. Key Takeaways

500K+ Students Use These Powerful Tools to Master Graphs of Projectile Motion Type 1: Dropping a projectile For their NSC Exams.

Other Revision Notes related to Graphs of Projectile Motion Type 1: Dropping a projectile you should explore

Displacement-Time Graph $(y-t)$

Velocity-Time Graph $(v-t)$

Acceleration-Time Graph $(a-t)$

Step 1: Find Final Velocity $(v_f)$

Step 2: Find Time $(\Delta t)$