Force in an elevator during acceleration

AI Thread Summary
The discussion revolves around calculating the reading on a scale in an accelerating elevator. A woman with a mass of 60.0 kg stands on the scale, while the elevator and scale together weigh 815 kg. The hoisting cable exerts a force of 9410 N during upward acceleration. To find the scale reading, one must determine the new acceleration using the equation F = ma, considering that the acceleration is greater than 9.8 m/s² due to the upward motion. The final scale reading reflects the increased force from the woman's weight combined with the additional force from the elevator's acceleration.
Strikersn
Messages
2
Reaction score
0

Homework Statement



A woman stands on a scale in a moving elevator. Her mass is 60.0 kg, and the combined mass of the elevator and scale is an additional 815 kg. Starting from rest, the elevator accelerated upward. During the acceleration, the hoisting cable applies a force of 9410 N. What does the scale read during the acceleration?

Homework Equations



F= ma

The Attempt at a Solution



9410 = 9.8(815 + 60) * a

I think the above equation is right, but not 100% on that. I can't figure out how to do the rest of this problem. Any help will be greatly appreciated. Thanks in advance!
 
Physics news on Phys.org
I believe you should solve the equation like this

F = m*a

since you are accelerating upwards a > 9.8m/s^2

Using the given force and the given weight you can find the "new" acceleration.

Using that acceleration you can find the force on the scale caused by the women.

Then using that force you can determine what her weight will show, (since you can assume the scale reads weights based off a = 9.8m/s^2, so a larger force will result in a larger weight)

Also, when you look at your above equation it is in the form F = m*a^2
 
Last edited:
Awesome! Thanks for helping me out!
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'Calculation of Tensile Forces in Piston-Type Water-Lifting Devices at Elevated Locations'
Figure 1 Overall Structure Diagram Figure 2: Top view of the piston when it is cylindrical A circular opening is created at a height of 5 meters above the water surface. Inside this opening is a sleeve-type piston with a cross-sectional area of 1 square meter. The piston is pulled to the right at a constant speed. The pulling force is(Figure 2): F = ρshg = 1000 × 1 × 5 × 10 = 50,000 N. Figure 3: Modifying the structure to incorporate a fixed internal piston When I modify the piston...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top