How Do You Calculate Penguin's Velocity on Frictionless Ice?

AI Thread Summary
To calculate the penguin's velocity on frictionless ice, the initial velocity in the x-direction is 0.41 m/s and remains constant, while the force from the wind in the y-direction results in an acceleration of 0.0784 m/s². The initial speed in the y-direction is zero, so the y-component of the velocity after 9.26 seconds can be calculated using the formula v = at, yielding a velocity of approximately 0.73 m/s in the y-direction. The final velocity is then found by combining the constant x-component and the calculated y-component. The correct magnitude of the penguin's velocity at t = 9.26 s is approximately 1.14 m/s, but it is essential to separate the x and y components for accurate results.
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A 3.7 kg penguin runs onto a huge sheet of frictionless Anarctic ice. At t=0 is is at x=0 and y=0 with an initial velocity of 0.41 m/s along the positive x-axis. It slides while being pushed by the wind with a force of 0.29 N directed along the positive y-axis. Calculate the magnitude of the penguin's velocity at t= 9.26 s.

I started this problem by first using Newton's 2nd Law to calculate the acceleration.
F=ma
.29 N= 3.7a
a= .0784 m/s^2

Then I used the equation v=v initial + at
v= .41 + .0784(9.26)
and got 1.14 m/s.

This wasn't right, can someone tell me what I'm doing wrong?

thanks in advance
 
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Punchlinegirl said:
I started this problem by first using Newton's 2nd Law to calculate the acceleration.
F=ma
.29 N= 3.7a
a= .0784 m/s^2
This is the acceleration in the y-direction.

Then I used the equation v=v initial + at
v= .41 + .0784(9.26)
and got 1.14 m/s.
You are mixing up x and y components. (The .41 is the x-component of the velocity, which remains constant.)

The initial speed in the y-direction is 0. Calculate the x and y components of the velocity separately, then combine them.
 
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