If a balloon is made of Mylar(alumized plastic) instead of rubber, would it stick to a wall if you rubbed the balloon against a wool sweater?
If a charged balloon is held a distance "d" above some paper bits they start to move. If the balloon is moved half as close, by how much has the force on the paper bits changed?
They probably mean aluminized Mylar.
Mylar itself is just the plastic film.
To the first question, the answer is probably no. The conducting metal layer would allow excess charge to go back to the wool. Try it and see, if you have any aluminized Mylar ballons around.
To the last question, consider the inverse square dependence upon distance in Coulomb's Law.
I totally forgot about that formula-so then the magnitude would be decreased by a factor of 1/2 raised to the second power- would it be 1/4 or .25
yes on #2, glad you remembered the Coulomb's Law formula
Thanks for confirming it
To answer the first question about the behavior of a Mylar balloon when rubbed against a wool sweater, we need to understand the concept of static electricity. When certain materials are rubbed together, like Mylar and wool, they can transfer electrons, leading to a build-up of static charge.
1. Gather materials: You will need a Mylar balloon, a wool sweater, and a wall or surface to test the balloon's behavior.
2. Rub the balloon on the wool sweater: Start by rubbing the balloon against the wool sweater, preferably for a few seconds. This process will generate static electricity on the surface of the balloon.
3. Test the balloon against a wall: Once the balloon is charged, bring it close to a wall and observe its behavior. If the static charge is strong enough, the balloon might stick to the wall for a short period of time. The attraction between the charged balloon and the wall may create a temporary sticking effect.
It's worth noting that while Mylar balloons can hold a static charge, they typically do not stick to surfaces as effectively as rubber balloons. This is because Mylar is a less adhesive material.
Moving on to the second question about the force change on paper bits when the charged balloon is moved closer:
1. Set up the experiment: Place some small paper bits or scraps on a flat surface. Make sure the surface is non-conductive, such as a tabletop or a plastic tray.
2. Charge the balloon: Rub the balloon against a wool sweater or any other material that can generate static electricity. This action will transfer charge to the balloon's surface.
3. Observe the paper bits' movement: Hold the charged balloon at a distance "d" above the paper bits and observe their behavior. The static charge on the balloon will induce an electric field, causing the paper bits to move towards or away from the balloon.
4. Move the balloon: Now, move the charged balloon to half the original distance, which is "d/2" in this case.
To calculate the change in force on the paper bits as the balloon is moved closer, you need to consider the inverse square law. The electric force between two charges decreases by the square of the distance between them.
Let's assume the force at distance "d" is represented as F1 and the force at distance "d/2" is represented as F2.
5. Calculate the force change: The change in force can be calculated using the formula:
Change in force = F2 - F1
However, since we know that the force between charges diminishes with the square of the distance, the relationship between F1 and F2 is:
F2 = (1/2)^2 * F1
Simplifying this equation, we get:
F2 = (1/4) * F1
Therefore, the change in force can be expressed as:
Change in force = (1/4) * F1 - F1
Simplifying further, we conclude that the force on the paper bits has decreased by 3/4 or 75% when the balloon is moved to half the original distance.