cq_1_131

Phy 121

Your 'cq_1_13.1' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.

** **

A ball rolls off the end of an incline with a vertical velocity of 20 cm/s downward, and a horizontal velocity of 80 cm/s. The ball falls freely to the floor 120 cm below.

• For the interval between the end of the ramp and the floor, hat are the ball's initial velocity, displacement and acceleration in the vertical direction?

#$&* Yes

• What therefore are its final velocity, displacement, change in velocity and average velocity in the vertical direction?

T=sqrt(2y/g)=4.9s

that would be so if its initial vertical velocity was zero, but it's not so in this case

100m/s(4.9)=x=490cm

Vf=0

Vavg=50m/s

• What are the ball's acceleration and initial velocity in the horizontal direction, and what is the change in clock time, during this interval?

#$&* V0=100m/s

A=100m/s/4.9=20.4cm/s^2

• What therefore are its displacement, final velocity, average velocity and change in velocity in the horizontal direction during this interval?

#$&* T=sqrt(2y/g)=4.9s

100m/s(4.9)=x=490cm

Vf=0

Vavg=50m/s

• After the instant of impact with the floor, can we expect that the ball will be uniformly accelerated?

#$&* Yes.

• Why does this analysis stop at the instant of impact with the floor?

• $&* that’s the final stop. Vf=0 and that is where the ball stops moving.

** **

15 minutes.

** **

I was slightly confused about this problem, and I don't think it's correct.

See my note, and then check the link. You should submit a revision for this one.

&#See any notes I might have inserted into your document. If there are no notes, this does not mean that your solution is completely correct.

Then please compare your solutions with the expanded discussion at the link

Solution

Self-critique your solutions, if this is necessary, according to the usual criteria. Insert any revisions, questions, etc. into a copy of this posted document. Mark any insertions with &&&& so they can be easily identified.

If your solution is completely consistent with the given solution, you need do nothing further with this problem. &#