kingflute
Badges: 0
Rep:
?
#1
Report Thread starter 2 years ago
#1
I have repeatedly tried to find a way to understand "forces in a lift" questions and have repeatedly failed. Can anyone help?
0
reply
the bear
Badges: 20
Rep:
?
#2
Report 2 years ago
#2
the reaction R of the floor on the passenger causes most problems...

if the lift has acceleration a then the net force on the passenger divided by the mass of the passenger ( including any parcels etc being carried ) must equal a.

the net force will be mg - R if the acceleration is downwards, and R - mg if the acceleration is upwards.
1
reply
atsruser
Badges: 11
Rep:
?
#3
Report 2 years ago
#3
(Original post by kingflute)
I have repeatedly tried to find a way to understand "forces in a lift" questions and have repeatedly failed. Can anyone help?
You need to understand the interactions of Newton's laws correctly. There's really nothing specific to forces in a lift. Maybe you could take a look at the Khan academy videos on Newton's laws?

It would be easier to explain if you put up a particular problem that you're having trouble with, too.
0
reply
kingflute
Badges: 0
Rep:
?
#4
Report Thread starter 2 years ago
#4
(Original post by atsruser)
You need to understand the interactions of Newton's laws correctly. There's really nothing specific to forces in a lift. Maybe you could take a look at the Khan academy videos on Newton's laws?

It would be easier to explain if you put up a particular problem that you're having trouble with, too.
It is as much knowing when to use overall forces or forces on an object in the lift or the lift itself, as anything else
0
reply
atsruser
Badges: 11
Rep:
?
#5
Report 2 years ago
#5
(Original post by kingflute)
It is as much knowing when to use overall forces or forces on an object in the lift or the lift itself, as anything else
This is too vague for me to comment on meaningfully. Put up a specific question, then someone can explain how things fit together more clearly. However, my previous comments still stand: you need to learn, and understand how to use, Newton's laws in general, not in some specific lift problem.
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

University open days

  • Bournemouth University
    Midwifery Open Day at Portsmouth Campus Undergraduate
    Wed, 18 Dec '19
  • The University of Law
    Open Day – GDL and LPC - Chester campus Postgraduate
    Sat, 4 Jan '20
  • University of East Anglia
    Mini Open Day Undergraduate
    Mon, 6 Jan '20

Did you vote in the 2019 general election?

Yes (425)
43.68%
No (103)
10.59%
I'm not old enough (445)
45.73%

Watched Threads

View All