# How Calculate Cat's Jump?

1. Nov 26, 2011

### PlaneWryter

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?

Best regards,
Plane Wryter

2. Nov 26, 2011

### Matterwave

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 $I=F_{tot}\Delta t=\Delta p$

3. Nov 26, 2011

### A.T.

4. Nov 26, 2011

### Dr_Morbius

Your cat only weighs 1 pound? How can a tiny kitten jump that high? My adult cat weighs 11 pounds.

5. Nov 27, 2011

### nucl34rgg

6. Nov 27, 2011