Verified Answer :

Sum the vector components:
Dx = 225 Cos(180)+ 78Cos(225)= -280.154 km
Dy = 225 Sin(180)+ 78Sin(225) = -55.154 km

displacement:
Sqrt(Dx^2+Dy^2) = 285.532 km
Arctan(Dy/Dx) = 191.137degrees CCW
OR:
11.137 degrees South of West

Displacement of the car is about 302 km at 13° south of west

Further explanation

Acceleration is rate of change of velocity.

\(\large {\boxed {a = \frac{v - u}{t} } }\)

\(\large {\boxed {d = \frac{v + u}{2}~t } }\)

a = acceleration ( m/s² )

v = final velocity ( m/s )

u = initial velocity ( m/s )

t = time taken ( s )

d = distance ( m )

Let us now tackle the problem !

Given :

d₁ = 225 km west

d₂ = 98 km southwest

Unknown :

displacement = d = ?

Solution :

\(d^2 = (d_1)^2 + (d_2)^2 + 2d_1d_2\cos 45^o\)

\(d^2 = (225)^2 + (98)^2 + 2(225)(98)\frac{1}{2}\sqrt{2}\)

\(d^2 = 60229 + 22050 \sqrt{2}\)

\(\large {\boxed {d \approx 302 ~km} }\)

\(\cos \theta = \frac{(d_1)^2+d^2-(d_2)^2}{2d_1d}\)

\(\cos \theta = \frac{225^2+302^2-98^2}{2(225)(302)}\)

\(\cos \theta \approx 0.974\)

\(\large {\boxed {\theta \approx 13^o} }\)

Conclusion :

Displacement of the car is about 302 km at 13° south of west

Learn more

  • Velocity of Runner : https://brainly.com/question/3813437
  • Kinetic Energy : https://brainly.com/question/692781
  • Acceleration : https://brainly.com/question/2283922
  • The Speed of Car : https://brainly.com/question/568302

Answer details

Grade: High School

Subject: Physics

Chapter: Kinematics

Keywords: Velocity , Driver , Car , Deceleration , Acceleration , Obstacle , Speed , Time , Rate

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