What is the Physics Behind a Cat's Jump?

  • Context: Undergrad 
  • Thread starter Thread starter PlaneWryter
  • Start date Start date
  • Tags Tags
    Jump
Click For Summary

Discussion Overview

The discussion centers around the physics of a cat's jumping ability, specifically how to calculate the force exerted during the jump and the duration of the jump. Participants explore concepts related to impulse, energy conservation, and the mechanics of jumping in relation to a cat's weight and jump heights.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant wonders how to calculate the force exerted by a cat during its jump, given its weight and the heights achieved.
  • Another participant suggests using energy conservation principles to determine the initial velocity required to reach the specified heights, referencing the equation \(\frac{1}{2}mv^2=mgh\).
  • A participant mentions that to calculate force, the duration of the force application is necessary, indicating that only impulse can be derived from the given information.
  • There are side comments about the weight of cats, with one participant expressing surprise at the weight of the cat mentioned, comparing it to their own heavier cat.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the calculations or methods to determine the force and duration of the jump. There are multiple viewpoints on how to approach the problem, and some participants engage in light-hearted commentary unrelated to the technical aspects.

Contextual Notes

Limitations include the need for assumptions about the duration of force application and the approximations involved in using energy conservation for the calculations.

PlaneWryter
Messages
1
Reaction score
0
Hello Physics Mavens,

Just watched one of my cats make two upward jumps; both with pinpoint accuracy.

(Cats are amazing creatures.)

One height was ~74cm above the floor; the other height ~81cm. He cleared both ledges by ~3cm and softly touched down on his paws at--what seems to be--near zero velocity.

In addition to being amazed by the accuracy of his internal computer...I wonder how one calculates the force he puts into each jump? Assuming there's a physics formula(s)--would you be so kind as to post an approach/solution?

CAT's weight: ~0.465kg
Height of First Ledge*: ~74cm
Height of Second Ledge*: ~81cm

*To clarify: He jumped from the floor to the first ledge...jumped back (down) to the floor...then jumped up to the second ledge--in this observation, he did not jump from the first ledge to the second.

If F = ma = gm; how much 'a' does he exert when leaving the ground such that his 'a' at (near) the desired height (+ ~3cm) approaches zero?

Also, is there a way to calculate the duration (time) of his jump?

Many, many thanks in advance.


Plane Wryter
 
Physics news on Phys.org
In order to get a force, you need to know for how long he applies this force. All you can get from the information given is the impulse (with a lot of approximations).

You can use energy conservation to get the initial velocity he needs to attain to reach the heights required: \frac{1}{2}mv^2=mgh. With this velocity, you know the change in momentum \Delta p = mv, and therefore the total impulse I=F_{tot}\Delta t=\Delta p
 
Your cat only weighs 1 pound? How can a tiny kitten jump that high? My adult cat weighs 11 pounds.
 
nucl34rgg said:
Those videos were so hilarious. I was laughing for like 5 minutes. :D
Then check out those:
http://www.theatlantic.com/video/archive/2011/09/can-an-astronaut-move-like-a-falling-cat/244829/
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
5K
  • · Replies 11 ·
Replies
11
Views
4K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 13 ·
Replies
13
Views
4K
  • · Replies 1 ·
Replies
1
Views
6K
  • · Replies 3 ·
Replies
3
Views
7K
  • · Replies 8 ·
Replies
8
Views
4K
  • · Replies 8 ·
Replies
8
Views
7K