the picture shows a physics lab set up.
why does the disc fall straight down into the glass when we quickly pull the index card away from the glass in a horizontal direction.
equolibrium
static friction
inertia
kinetic friction
The reason the disc falls straight down into the glass when the index card is quickly pulled away from the glass in a horizontal direction is due to inertia. Inertia is the property of matter that resists changes in its state of motion. When the card is quickly pulled away, the disc tends to maintain its state of rest or motion (in this case, at rest on the card) due to inertia. As a result, the disc continues moving horizontally for a brief moment until the force of gravity overcomes the inertia, causing it to fall straight down into the glass. Static friction and kinetic friction do not play a significant role in this scenario as the disc falls freely due to gravity. Equilibrium, the state of balance or stability, is not relevant in this context.
The reason why the disc falls straight down into the glass when you quickly pull the index card away from the glass in a horizontal direction can be explained by the concept of inertia.
Inertia is the tendency of an object to resist changes in its motion. When you pull the index card horizontally, you apply a force to the disc. However, because of its inertia, the disc tends to maintain its current state of motion, which is at rest.
As a result, when the index card is removed, the force pulling the disc forward is no longer present, and the disc remains stationary due to its inertia. Gravity then acts on the disc, causing it to fall straight down into the glass.
Therefore, the correct answer is inertia.
In this physics lab setup, when you quickly pull the index card away from the glass in a horizontal direction, the disc falls straight down into the glass due to inertia.
Inertia is the tendency of an object to resist changes in its state of motion. According to Newton's first law of motion, an object at rest will remain at rest, and an object in motion will continue moving in a straight line at a constant speed, unless acted upon by an external force.
In this case, before you pull the card, the disc is at rest on top of the card, and both the disc and the card are not moving vertically. When you quickly pull the card horizontally, the card moves away, but the disc tends to resist this change in motion due to its inertia.
The downward force of gravity still acts on the disc, pulling it vertically downwards. Therefore, while the card moves horizontally, the disc remains in its initial vertical position momentarily due to inertia. As a result, it appears as if the disc falls straight down into the glass.
It is important to note that equilibrium, static friction, and kinetic friction do not play a significant role in causing the disc to fall straight down in this scenario.