A plane heads due north at 85 km/h and is being blown due west at 45 km/h. How would you calculate the resultant velocity of the plane?

a. Since the two velocity components are parallel we can calculate the resultant velocity using the Pythagorean theorem.

b. Since the two velocity components are perpendicular we can calculate the resultant velocity using the Pythagorean theorem.

c. Since the two velocity components are perpendicular we can calculate the resultant velocity using the Kinematic equation.

d. Since the two velocity components are parallel we can calculate the resultant velocity using the cosine function.

1 answer

To calculate the resultant velocity of the plane, we need to consider the two velocity components: the plane's velocity heading due north and the velocity of the wind blowing due west. These two components are perpendicular to each other.

Given that:

  • The plane's northward velocity = 85 km/h (vertical component)
  • The wind's westward velocity = 45 km/h (horizontal component)

Since these components are perpendicular, we can use the Pythagorean theorem to find the resultant velocity.

The correct choice is:

b. Since the two velocity components are perpendicular we can calculate the resultant velocity using the Pythagorean theorem.

The resultant velocity \( R \) can be calculated using the formula:

\[ R = \sqrt{(V_n)^2 + (V_w)^2} \]

Where \( V_n = 85 \) km/h (northward component) and \( V_w = 45 \) km/h (westward component).

So,

\[ R = \sqrt{(85)^2 + (45)^2} = \sqrt{7225 + 2025} = \sqrt{9250} \approx 96.2 , \text{km/h} \]

Thus, the resultant velocity of the plane is approximately 96.2 km/h.