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please help me work through this! I'm just a bit stuck and think help would make me better understand

please help me work through this! I'm just a bit stuck and think help would make me-example-1
User Cliff AB
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1 Answer

3 votes

Answer:

Given equation of motion of a particle is,


s(t)=4t^3+36t^2+96t

To find the velocity function of t, value of t when the velocity is zero and acceleration of the particle.

Step-by-step explanation:

we know that, velocity of a particle is rate of change of the object’s position with respect to a frame of reference and time.

we get,


v(t)=(d)/(dt)(s(t))

Substitute for s(t), we get


v(t)=(d)/(dt)(4t^3+36t^2+96t)

Differenting we get,


v(t)=12t^2+72t+96

Required velocity function is,


v(t)=12t^2+72t+96

when velocity equal to 0, we get


12t^2+72t+96=0

Dividing by 12, we get


t^2+6t+8=0

we get,


t^2+4t+2t+8=0
t(t+4)+2(t+4)=0

Taking (t+4) as common we get,


(t+4)(t+2)=0

we get,


t=-4,-2

The values of t are,

t=-4 and t=-2

To find acceleration of a particle.

we know that,

Acceleration a(t) is the rate at which velocity (speed) is changing.

we get,


a(t)=(d)/(dt)(v(t))

Substitute v(t), we get,


a(t)=(d)/(dt)(12t^2+72t+96)

we get,


a(t)=24t+72

The acceleration of a particle is,


a(t)=24t+72

User Rzv
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