Question

Supposing there's a truck of mass M carrying birds of total mass m. If all the birds start flying, what'll be effective weight the ground under the truck will experience?

Answer 1

if the birds will start flying they apply a force downwards and the force applied is equal to the change in momentum

so if the birds fly with a velocity of v
then the change in momentum = mv

force applied = mv
total force = force applied by birds + force of the truck
= mv+Mg

Answer 2

(m+M)g
because even though the birds are flying, the force that they apply on the floor of the truck would be equal to m

Answer 3

thanks guys, :D