Find "x" for Pulley Problem of 5kg & 1kg Masses

Click For Summary
In the pulley problem, there are two masses: 5 kg and 1 kg, with the heavier mass being doubled. The goal is to find the downward acceleration "x" of the 10 kg mass when gravitational acceleration (g) is 10 m/s². Participants suggest using the formula F = ma for both masses, emphasizing the need to include tension in the calculations. The initial calculations of forces are clarified as being related to weight rather than net force. The discussion focuses on correctly applying physics principles to solve for "x."
jk13
Messages
3
Reaction score
0


There are two bodies of mass 5kg and 1 kg on either sides of a pulley. (The string stays vertical and straight at all times). The heavier mass is doubled. The downward acceleration on the string of the hevier mass is "x". Find "x" when g=10m/s-2.
Please help fast!
Desperate!
 
Physics news on Phys.org
welcome to pf!

hi jk13! welcome to pf! :smile:

(try using the X2 button just above the Reply box :wink:)
jk13 said:
There are two bodies of mass 5kg and 1 kg on either sides of a pulley. (The string stays vertical and straight at all times). The heavier mass is doubled. The downward acceleration on the string of the hevier mass is "x". Find "x" when g=10m/s-2.

(what do you mean by "The heavier mass is doubled" ? :confused:)

call the tension "T", and do F = ma twice, once for each mass …

show us what you get :smile:
 


The mass 5 kg is doubled. :p
f=ma
f=5*10=50
f=1*10=10
Correct?
 


Help me please?! :(
 
hi jk13! :smile:
jk13 said:
f=ma
f=5*10=50
f=1*10=10

no, that's weight = mg

you need Ftotal = ma, and you need to include the tension, T, and the acceleration, a
 
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?

Similar threads

  • · Replies 5 ·
Replies
5
Views
1K
  • · Replies 15 ·
Replies
15
Views
6K
  • · Replies 18 ·
Replies
18
Views
4K
  • · Replies 17 ·
Replies
17
Views
3K
  • · Replies 10 ·
Replies
10
Views
5K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 22 ·
Replies
22
Views
6K
  • · Replies 22 ·
Replies
22
Views
1K
  • · Replies 18 ·
Replies
18
Views
1K