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A woman walks 250 m in the direction 48° east of north, then 165 m directly east. Find (a) the magnitude and (b) the angle (from due east) of her final displacement from the starting point. (c) Find the distance she walks.

Respuesta :

Answer:

a) magnitude of direction = 387.92m

b)Angle of displacement = 25.54°

c) Total distance=415m

Explanation:

Let +x axis be east

Let +y axis be north

d1=250<(90-48)= 250<42°

d2=165<0°

Remember all angles are measured anti clockwise in +axis

total =(250cos42° + 165cos0°)I + (250sin42°)j

dtotal= 350i (m) + 167.28j(m)

/dtotal/ =sqrt(350^2 + 167.28^2)

/dtotal/= sqrt150482.59

/dtotal/= 387.92m

b) Theta = Tan^-1(167.28/350)

Theta = tan^-1 0.5779

Theta= 25.54°

c)Total distance covered by the woman =250+165= 415m

Answer:

(a)  [tex]Magnitude=380.69[/tex]

(b) [tex]Angle=29.21^{o}[/tex]

(c) [tex]Distance=415m[/tex]

Explanation:

Given data

The Woman walks 250m in 48° east of north

Then 165m due to east

Let east be the +x axis and the north is +y direction

So the two displacements is written in polar form as:

d₁=250∠(90°-48°)=250∠42°

d₂=165∠0°  

All angles are measured in counterclockwise from +x direction

So the total displacement is given dot product as:

[tex]d_{dot}=d_{1}.d_{2}\\d_{dot}=(250Cos(48^{o} )+165Cos(0_{o} ))i+(250Sin(48^{o} )j) \\d_{dot}=332.28(m)i+185.786(m)j[/tex]

Part (a)

The magnitude of women total displacement

[tex]|d_{dot} |=\sqrt{(332.28)^{2} +(185.786)^{2} } \\|d_{dot} |=380.69[/tex]

Part (b)

The angle of woman displacement from her starting point is

[tex]\alpha =tan^{-1}(\frac{185.786}{332.28} )\\\alpha =29.21^{o}[/tex]

Part (c)  

The Total distance that the women walks is given as:

[tex]distance=250m+165m\\distance=415m[/tex]