<p>In a test experiment on a model aeroplane in wind tunnel, the flow speeds on the upper and lower surfaces of the wings are 70&nbsp;<span class="equation">\(ms^{-1}\)</span>&nbsp;and 65 <span class="equation">\(ms^{-1}\)</span>&nbsp;respectively. If the wing area is&nbsp; 2<span class="equation">\(m^2\)</span>, the lift of the wing is _________ N.</p>

<p>(Given density of air = 1.2 kg <span class="equation">\(m^{-3}\)</span>​​​​​​​)​​​​​​​​​​​​​​</p>