# Physics

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An ant on a picnic table travels 3.0 * 10^1 cm eastward, then 25 cm northward, and finally 15 cm westward. What is the magnitude of the ant's displacement relative to its original position

i got 70 cm

For the winter, a duck flies 10.0 m/s due south against a gust of wind with a speed of 2.5 m/s. What is the resultant velocity of the duck?

:)

• Physics - ,

70 cm is the distance, not displacement. His travels are vectors, and you have to add them as vectors.

He is flying at 10relative to the wind, but the wind is pushing him back at 2.5.

HMMMM. What do you think.

• Physics - ,

For the first one, I don't think it would be as much as 70 cm because as you're moving, you make an almost complete shape of a trapezoid. When it says "relative to its original position", it means from the starting point you find the distance, so it'll be I think around 30 cm but you'll probably have to be more exact.

For the second problem, you also find the difference between the two velocities to find the resultant velocity of the duck. Here, the duck's velocity would be 7.5 m/s because the wind is slowing him down.

• Physics - ,

7.5 m/s south?

• Physics - ,

Emily is a physics whiz.

• Physics - ,

Haha thanks :)

• Physics - ,

for the first one find the amount moved total east west.
Movement lateral=(east)- (west)
30cm - 15cm = 15 cm
now find the longitudinal movement
Movement longitudinal = 25 cm
the maginitude is the distance moved relative to original postion which is given by the distance formula
d= (x^2 + y^2)^(1/2)
where x is movement lateral and y is movement longitudinal
d= (15^2 + 25^2)^(1/2)

• Physics - ,

29cm at 59 degress North of East