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

[boneill3]

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

 

[Andrew Mason]

Look at it from the point of view of energy - potential and kinetic.

AM

 

[E=mc^84]

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

 

[beetle2]

So,
vfinal^2 = Vinitial^2 - 2gx
Vinitial^2= 0 + 2gx
= 0 + 2*9.8
= 19.6m/s^2

 

[E=mc^84]

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