Initial Velocity of Dog Jumping 0.20 m: 0 m/s

AI Thread Summary
To determine the initial velocity of a dog jumping to a height of 0.20 m, the relevant equations of motion and gravitational acceleration are applied. The final velocity at the peak of the jump is 0 m/s, and using the formula v_final^2 = v_initial^2 - 2gx, the initial velocity can be calculated. The correct approach leads to the conclusion that the initial velocity is approximately 2 m/s, derived from the equation sqrt(2gx) where g is 9.8 m/s². Misinterpretations regarding the variables and calculations were clarified throughout the discussion. Ultimately, the initial velocity required for the jump is confirmed to be 2 m/s.
boneill3
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Homework Statement


A dog can jump to a height of 0.20 m. What is the initial velocity of the dog?

Homework Equations



v=v0+at

The Attempt at a Solution



I'm not sure if this is suppose to be a trick question. Are they talking about the gravitational acceleration?

v=v0+at

v0= 0
t=0
a=(-g)=-9.8m/s2


v=0+-9.8 * 0
v=0
 
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Look at it from the point of view of energy - potential and kinetic.

AM
 
boneill3 said:

Homework Statement


A dog can jump to a height of 0.20 m. What is the initial velocity of the dog?

Homework Equations



v=v0+at

The Attempt at a Solution



I'm not sure if this is suppose to be a trick question. Are they talking about the gravitational acceleration?

v=v0+at

v0= 0
t=0
a=(-g)=-9.8m/s2


v=0+-9.8 * 0
v=0

No, you have to find Vo. Yes, you use gavitatinal accelertion cus the dog jumps vertically.
use: vfinal^2 = Vinitial^2 - 2gx, Vfinal = 0 since the dog comes to an abrupt stop at the 0.2m height. Therefore, solve for Vinitial.

Hope this helps;0
 
So,
vfinal^2 = Vinitial^2 - 2gx
Vinitial^2= 0 + 2gx
= 0 + 2*9.8
= 19.6m/s^2
 
beetle2 said:
So,
vfinal^2 = Vinitial^2 - 2gx
Vinitial^2= 0 + 2gx
= 0 + 2*9.8
= 19.6m/s^2


NO, Vinitial shud equal = sqrt2gx = sqrt2x9.8x0.2 = 2m/s
 
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