Thames & Kosmos DLX, Experiment Manual, Page: 94 / 132

How a dump truck works
YOU WILL NEED
› The assembled dump truck
› IR remote control
› 5 AA batteries or 5 AA rechargeable batteries
› Pieces from the experiment kit to serve as boundary
markers
› Ruler
› Masking tape
HERE’S HOW
1. Use extra pieces from your experiment kit to make a
parking space into which your dump truck can fit
lengthwise.
2. Lay a ruler across the cargo bed. The ruler has to be
long enough to extend beyond the bed to the left and
right.
3. Drive toward the parking space from a far-away
starting spot and back into it.
4. Tip up the cargo bed so the ruler slides off it.
5. The experiment will be harder if you specify a small
marked area as a “landing zone” for the ruler. Use
masking tape to mark a landing zone behind the
parking space.
6. The better you get at unloading, the smaller you can
make the landing zone.
WHAT’S HAPPENING
A dump truck is a special
construction truck with an open-
box bed on it. It is ideal for loose,
pourable material such as soil or sand. Since the
dumping bed — just like an inclined plane — can
be tilted, the material can just slide off the cargo
bed all by itself if the bed is tilted enough. That
makes unloading very easy.
KEYWORD: INCLINED PLANE
An inclined plane is always used when an
object (or person) is to be transported
upward with relatively little expenditure
of force. Examples might be a ramp or an
uphill-climbing road with switchbacks.
Slides and peaked roofs are inclined
planes too.
You have probably noticed how easy
the dump truck is to drive. Why not try using it as
a replacement vehicle in other experiments?
Experiment 12 or 15, for example.
WANT MORE?
EXPERIMENT 14
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