Look Who it Was Random video

15x15x15 #8 Equal and opposite - crossbow car

1,457 views · Published 15 December 2013 · 11:44 · Indexed 22 September 2026

Channel: GrandadIsAnOldMan · 2013 · Science & Technology

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The best way to describe this car is as a crossbow in reverse. When you fire the bolt (the lead weight) it stays where it is and the crossbow (the car) flies across the room.
In truth the bolt does move, but the distance it travels is tiny compared to the distance travelled by the car.
Mohammed Dalaf commented that he had a project where the car needed to be 15cm by 15cm by 15cm and that inspired me to see what I could make that fitted that specification. This is my eighth attempt.

I cast a weight from molten lead. This needs supervision as there are many dangers involved.

After I made this video I modified it without the 15x15x15 restrictions and it worked better
https://youtu.be/64Xm9FlLqGY

Main components are
-
Plastic tray
DVD player feet for wheels
2 discs cut from credit cards for wheels
2 Barbecue skewers
Lead weight
Flower cane
Rubber bands

Main tools
-
Sharp knife
Hot glue gun
Drill

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