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I really need some help with this one:

An unhappy rodent of mass 0.307kg , moving on the end of a spring with force constant 2.48N/m , is acted on by a damping force Fx=−b⋅vx.

Part A

If the constant b has the value 0.894kg/s , what is the frequency of oscillation of the mouse?

Part B

For what value of the constant b will the motion be critically damped?

F = -kx

F = mg

f = 1/T = ω/2π

Part A:

Fx = -bvx = -0.894⋅vx

-kx = F => m⋅a = -k⋅x, and I put the numbers in and got:

0.307⋅9.81 = -2.48⋅x => x = -1.214 m

ω = sqrt(k/m), and I put the numbers in and got: ω = 0.452 rad/s

Then I tried to calculate vx by:

vx⋅(-0.894)=3.0117 => vx = -3.369 m/s

I don't know what to do. Thankful for all help I can get!

I really need some help with this one:

1. Homework Statement1. Homework Statement

An unhappy rodent of mass 0.307kg , moving on the end of a spring with force constant 2.48N/m , is acted on by a damping force Fx=−b⋅vx.

Part A

If the constant b has the value 0.894kg/s , what is the frequency of oscillation of the mouse?

Part B

For what value of the constant b will the motion be critically damped?

## Homework Equations

F = -kx

F = mg

f = 1/T = ω/2π

## The Attempt at a Solution

Part A:

Fx = -bvx = -0.894⋅vx

-kx = F => m⋅a = -k⋅x, and I put the numbers in and got:

0.307⋅9.81 = -2.48⋅x => x = -1.214 m

ω = sqrt(k/m), and I put the numbers in and got: ω = 0.452 rad/s

Then I tried to calculate vx by:

vx⋅(-0.894)=3.0117 => vx = -3.369 m/s

I don't know what to do. Thankful for all help I can get!

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