# Help with a confusing free-fall motion physics problem?

• Jrohazn
In summary, the conversation is about a physics problem involving two individuals, West and Lindsay, dropping rocks from a building. The question is asking for the common height from which the rocks were released. The equation y=y0+vo(t)-1/2(g)t^2 is mentioned but the person is confused on how to set up Lindsay's equation and whether the initial velocity should be positive or negative. They are seeking clarification and advice on how to approach the problem without looking at others' answers.
Jrohazn
I'm taking physics for the first time, and I've been attempting the textbook problems, but I can't seem to get it.

1. West stands on the roof of a building, leans over the edge and drops a rock. Lindsay waits 1.25 s after West releases his rock and throws her own rock straight down at 28.0 m/s. Both rocks hit the ground simultaneously. Calculate the common height from which the rocks were released.
2. y=y0+vo(t)-1/2(g)t^2
I'm honestly not even sure how to do it. For Wes: 0=y0-1/2(g)t^2; y0=1/2gt^2
I'm confused on how to set up Lindsay's equation. I checked other people's answers on chegg, and they seem to set up vo as a positive vector, but I thought that since she's throwing down, that it would be negative? Can someone clear that up for me? And for time, would it be (1.25+t)?

I suggest you do not look at other people's answers and try to solve it yourself by thinking instead.

How would you set up the equation that determines how long it takes for Lindsay's rock to hit the ground?

## 1. What is free-fall motion in physics?

Free-fall motion in physics is the motion of an object falling under the influence of gravity, with no other forces acting upon it. This means that the only acceleration acting on the object is the acceleration due to gravity, which is 9.8 m/s².

## 2. How do I calculate the distance traveled during free-fall?

The distance traveled during free-fall can be calculated using the equation d = 1/2 * g * t², where d is the distance, g is the acceleration due to gravity, and t is the time in seconds.

## 3. What is the difference between free-fall and uniformly accelerated motion?

The main difference between free-fall and uniformly accelerated motion is that in free-fall, the only force acting on the object is gravity, whereas in uniformly accelerated motion, there may be other forces acting on the object.

## 4. How does air resistance affect free-fall motion?

Air resistance, also known as drag, can affect free-fall motion by slowing down the object's fall. This is because air resistance is a force that acts in the opposite direction of the object's motion, causing it to experience a lower acceleration and therefore fall more slowly.

## 5. What are some real-life examples of free-fall motion?

Some common real-life examples of free-fall motion include objects falling from a height (such as a skydiver), a ball being dropped from a height, and a person jumping off a diving board. In each of these scenarios, the object is only affected by the force of gravity and experiences free-fall motion.

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