Acceleration in an Elevator: Solving Newton's Second Law Problem

Click For Summary
To solve the problem involving Newton's Second Law in an elevator scenario, begin by analyzing the forces acting on the student at different points in the elevator's motion. The student's weight readings indicate variations in acceleration: an increase to 1050 N suggests upward acceleration, while a drop to 588 N indicates downward acceleration. Use the equation for acceleration, which is net force divided by mass, applying the gravitational force equation as needed. Drawing free-body diagrams for each situation will help clarify the forces involved. This structured approach will lead to determining the acceleration at both the beginning and end of the elevator trip.
hghwinds
Messages
2
Reaction score
0
Hi, I'm having trouble with a problem dealing with Newton's Second Law, and was wondering if anyone could give me a hint as to how I should solve it (general equation, process, whatever)? I'm not asking for somebody to solve it, I just need some help...:smile:


Homework Statement


A student, standing on a scale in an elevator at rest, sees that his weight is 840 N. As the elevator rises, his weight increases to 1050 N, then returns to normal. When the elevator slows to a stop at the 10th floor, his weight drops to 588 N, then returns to normal. Determine the acceleration at the beginning and end of the trip.

Homework Equations



acceleration= net force/mass and maybe Fg= ge * mass

The Attempt at a Solution

 
Physics news on Phys.org
This is a two part problem: treat the beginning and end of the trip as two separate problems. For each situation, draw a free-body diagram of the forces acting on ElevatorMan, then algebraically add up the forces associated with each arrow.
Welcome aboard, and hope that helps!
 
Alright, thanks so much!
 

Thread 'Magnitude of buoyant force in fluids of different densities'

The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?
View full post »

Similar threads

Having a hard time learning Newton's 2nd law
  • · Replies 5 ·
Replies
5
Views
2K
Rocket acceleration problem: confused about Newton's 2nd Law
  • · Replies 42 ·
2
Replies
42
Views
6K
Rank forces according to magnitude: Newton's 2nd/3rd laws
  • · Replies 5 ·
Replies
5
Views
7K
Newton's law problem: Helicopter lifting a box with a rope
  • · Replies 5 ·
Replies
5
Views
3K
Unbalanced force to find altitude of airplane
  • · Replies 4 ·
Replies
4
Views
2K
Newton's law problem: Pushing 2 stacked blocks on a horizontal table
  • · Replies 13 ·
Replies
13
Views
3K
Newton's laws — Two stacked blocks sliding on a frictionless floor
  • · Replies 17 ·
Replies
17
Views
3K
Conceptual questions about Newton's Laws....
  • · Replies 15 ·
Replies
15
Views
4K
Two forces acting on an object given in vectors - SOLVED
  • · Replies 1 ·
Replies
1
Views
1K
Solving Spool Acceleration Problem Using Newton's Laws
  • · Replies 12 ·
Replies
12
Views
3K