A helicopter has a speed in calm air of 170 kmh- and it's travelling on a bearing of 120° relative to the air. The wind is blowing at a speed of 30 kmh from the south-west. Take unit vectors i to point east and j to point north. (a) Express the original velocity b of the helicopter relative to the air and the velocity w of the wind in component form, giving the numerical values in km h-1 to two decimal places. (b) Express the resultant velocity v of the helicopter in component form, giving numerical values in km h-¹ to two decimal places. (c) Hence find the magnitude and direction of the resultant velocity v of the helicopter, giving the magnitude in km h−¹ to one decimal place and the direction as a bearing to the nearest degree.

A helicopter has a speed in calm air of 170 kmh- and it's travelling on a bearing of 120° relative to the air. The wind is blowing at a speed of 30 kmh from the south-west. Take unit vectors i to point east and j to point north. (a) Express the original velocity b of the helicopter relative to the air and the velocity w of the wind in component form, giving the numerical values in km h-1 to two decimal places. (b) Express the resultant velocity v of the helicopter in component form, giving numerical values in km h-¹ to two decimal places. (c) Hence find the magnitude and direction of the resultant velocity v of the helicopter, giving the magnitude in km h−¹ to one decimal place and the direction as a bearing to the nearest degree.