# Physics Problems ? (particle acceleration)

• JJ91284
In summary: The plane is accelerating you along with the pendulum (you are not stationary).4. The plane has been accelerating you for a finite amount of time.5. The magnitude of the acceleration vector is (9.8 m/s2). 6. The vector has a magnitude of (100 m/s). In summary, -A particle experiences a constant acceleration that is north at 100 m/s2. -At t = 0, its velocity vector is 45 m/s east. -At what time will the magnitude of the velocity be 100 m/s? -The acceleration vector has a magnitude of (100 m/s).
JJ91284
Physics Problems ? (particle acceleration)

I'm working on my last 2 of 30 or so physics problems and am pretty lost on what to do/how to even start. The homework is due in exactly 3 hrs, I already have an "A" on this assignment but would like to squeeze on these last 6 points or so.

Question 6

A particle experiences a constant acceleration that is north at 100 m/s2. At t = 0, its velocity vector is 45 m/s east. At what time will the magnitude of the velocity be 100 m/s?

Question 7

An accelerometer-a device to measure acceleration-can be as simple as a small pendulum. Suppose you are flying a small plane in a straight horizontal line and your accelerometer hangs 11° behind the vertical, opposite the direction of motion. What is your acceleration?

What are your thoughts so far?

Hints:

Qu #6: You're given the component of velocity in the east direction and the magnitude of the velocity at a certain time, how can you work out the north component?

Qu #7: Draw a free body diagram of the pendulum and see if you can work from there.

Question 6 I don't really understand what they are trying to get across.

So a particle is going N at 100 ms^2

So that gives me acceleration is=100 constantly

It gives me east velocity at 45 m/s at t=0 (time)

I'm assuming the North part is important, but I don't know what equation they're looking for or what in general I'm suppose to find.

As far as question 7 goes, am I suppose to use gravity (9.8 m/s2) for anything. The plane is obviously accelerating because the pendulum is back 11 degrees. Just like when a car accelerates, your pushed into the seat.

I was thinking of accelerating formulas I know, and a=v/t doesn't work. I don't have velocity or time. The only component that I feel I have would be the angle which is 11 degrees. Which I don't know what I'm suppose to use that for.

I guess there were a lot of students confused on question 7 so this is what are instructor said.

HW problems from Chapter 3 Hint for Problem 7: The tension on the pendulum string has an x and y component, the y component is T cos theta and is equal to mg - use this to solve for T. The x component is balanced by the forward acceleration of the airplane - so use T sin theta - a*m to find a.

I'm going to see if I can figure it out now.

Acceleration vectors can be added together using the same math as you've been using to add velocity vectors. You do not need to really break the components up into x-y, because you already know the direction of the acceleration!

1. Due to gravity directly down (-y).
2. Due to the plane directly to the back (-x).

## 1. What is particle acceleration?

Particle acceleration is the change in velocity of a particle over time. It is a measure of how quickly the speed of a particle changes.

## 2. How is particle acceleration calculated?

Particle acceleration can be calculated by dividing the change in velocity by the change in time. This can be expressed as a = (vf - vi) / t, where a is acceleration, vf is final velocity, vi is initial velocity, and t is time.

## 3. What is the difference between average and instantaneous acceleration?

Average acceleration is the change in velocity over a period of time, while instantaneous acceleration is the change in velocity at a specific moment in time. Average acceleration is calculated using the average velocity over a period of time, while instantaneous acceleration is calculated using the velocity at a specific point in time.

## 4. How does particle acceleration relate to Newton's laws of motion?

Particle acceleration is directly related to Newton's second law of motion, which states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. This means that the greater the force applied to a particle, the greater its acceleration will be. Additionally, Newton's first law of motion states that an object will remain at rest or in uniform motion unless acted upon by an external force, which also applies to particles and their acceleration.

## 5. Can particle acceleration be negative?

Yes, particle acceleration can be negative. This means that the particle is slowing down in the direction of its motion. It can also be positive, indicating that the particle is speeding up in the direction of its motion.

• Introductory Physics Homework Help
Replies
7
Views
2K
• Introductory Physics Homework Help
Replies
42
Views
3K
• Introductory Physics Homework Help
Replies
15
Views
2K
• Introductory Physics Homework Help
Replies
3
Views
1K
• Introductory Physics Homework Help
Replies
5
Views
468
• Introductory Physics Homework Help
Replies
9
Views
851
• Introductory Physics Homework Help
Replies
11
Views
917
• Introductory Physics Homework Help
Replies
7
Views
875
• Introductory Physics Homework Help
Replies
4
Views
523
• Introductory Physics Homework Help
Replies
26
Views
2K