contestada

A car travels 10 km southeast and
then 15 km in a direction 60° north of
east. Find the magnitude of the car's
resultant vector.
[?] km
Round to the nearest tenth.

Respuesta :

Starrysoul100

[tex]\bold{\huge{\green{\underline{Solution}}}}[/tex]

  • A car travels 10 km southeast and then 15 km in a direction 60° north of east

[tex]\bold{\underline{ To\: Find }}[/tex]

  • We have to find the magnitude of the car of resultant vector

[tex]\bold{\underline{ Let's \: Begin }}[/tex]

Here,

  • In South east, car travels = 10km

  • In North of east, it travels = 15km

  • Angle between south east and north east is 60°

Therefore,

According to parallelogram law of resultant vector

If two vectors are represented by two adjacent sides of a parallelogram drawn from a point , the their resultant is equal to the diagonal of the parallelogram.

That is,

[tex]\sf{ R = AC^{2}= A^{2}+ B^{2}}[/tex]

But, we have to calculate the magnitude of the resultant vector

[tex]\sf{ | R |= √A^{2}+ B^{2}+ 2ABCos{\theta} }[/tex]

Subsitute the required values,

[tex]\sf{ | R |=\sqrt{ (10)^{2} + (15)^{2} + 2× 10 × 15 × cos 60{\degree}}}[/tex]

[tex]\sf{ | R | =\sqrt{ 100 + 225 + 20 × 15 × 1/2}}[/tex]

[tex]\sf{ | R | = \sqrt{100 + 225 + 10 × 15 }}[/tex]

[tex]\sf{ | R | = \sqrt{335 + 150 }}[/tex]

[tex]\sf{ | R | = \sqrt{485 }}[/tex]

[tex]\sf{\red{ | R | = 22.02 \: km}}[/tex]

Hence, The magnitude of the car resultant vector is 22.02 km.