1. Pushing a door open is an example of mechanical force. The force you apply to the door is transmitted through the door to the hinges, which then rotate and allow the door to open.

2. Lifting a book is another example of mechanical force. The force you apply to the book is transmitted through your hand and arm to the book, which then moves upwards.

3. Riding a bike is a third example of mechanical force. The force you apply to the pedals is transmitted through the chain to the wheels, which then rotate and propel the bike forward.