Calculating Final Speed and Direction of a Moving Object in a Collision

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A force of 1200N is applied to a 0.4kg steel ball moving at 14m/s during a 27ms collision, opposing its initial velocity. The impulse-momentum principle is used to calculate the final speed. The calculations show that the final speed is 67m/s after accounting for the force applied. The direction of the ball reverses due to the opposing force. The final speed and direction are confirmed as correct.
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Homework Statement


A force that averages 1200N is applied to a 0.4kg steel ball moving at 14m/s in a collision lasting 27ms. If the force is in a direction
opposite the inital velocity of the ball ,find the final speed and direction of the ball


Homework Equations



n/a

The Attempt at a Solution


I used FdeltaT=mv
1200(27x10^-3)=0.4(v2-v1)
32.4=0.4v2-5.6
38/0.4=v2
95m/s =V2. Is this correct?
 
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Fdt = Δp is a vector equation.
You have defined the impulse FΔt as positive, so v1 is negative.
 
rude man said:
Fdt = Δp is a vector equation.
You have defined the impulse FΔt as positive, so v1 is negative.

so it would be 32.4-5.6=26.8
26.8/0.4=67m/s?
Is this right?
 
vongola13th said:
so it would be 32.4-5.6=26.8
26.8/0.4=67m/s?
Is this right?

Yes it is.
 
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