A Little Girl Sits in a Car at a Traffic

question 100

Multiple Choice

A little girl sits in a car at a traffic light holding a helium-filled balloon as shown in the illustration below. The windows are closed and the car is relatively airtight. When the light turns green and the car accelerates forward, her head pitches backward but the balloon pitches forward. Why?

• A)This demonstration will only work with a helium filled mylar balloon since the mylar is unaffected by the motion of the air moving backwards inside the car.
• B)Since helium is lighter than air, it will follow the path of the car and not the direction of movement of the air within it.
• C)Since the car is relatively airtight and the balloon is not anchored to the car, the balloon will be unaffected by the acceleration of the car.
• D)The air inside the car has more inertia than the helium in the helium balloon. Therefore, although the air pitches backwards, the lighter helium moves forward.

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Definitions:

THC

Tetrahydrocannabinol, the psychoactive component of cannabis responsible for its mind-altering effects.

Psychoactive Chemical

A substance that changes brain function and results in alterations in perception, mood, consciousness, cognition, or behavior.

Drug Dependence

A condition where an individual feels compelled to continuously use drugs in order to function normally, often accompanied by physical or psychological addiction.

Physiological Functioning

The activities and processes of the body's systems and organs that are necessary for maintaining life and health.