posted by Tebogo on .
1.A hot air balloon is rising upwards at a constant velocity of 5m.s when the balloon is 100m above the ground, a sandbag is dropped from it. 1.1 what is the magnitude of the acceleration of:a)The hot-air balloon while the sandbag is in it.b)The sandbag the moment is dropped from the hot air balloon.
1.1 a). They say it is rising at constant velocity before the bag drops. That information contains your answer.
1.1 b) You need to provide more information, preferably the mass of the sandbag and the rest of the balloon.
The acceleration of the balloon at any time is Fnet/M. The drag force and buoyancy do not instanteously change but the weight force and the mass do change.
The new value of a (upward) is
Ms*g/(M - Ms)
= g/[(M/Ms) -1)]
Knowing the velocity before dropping won't tell you anything about M and Ms.
1.1 the balloon is rising upwards acceleration is always downwards so therefore the magnitude of acceleration is 9.8 ms^-2 downwards.
Alternatively at constant velocity, acceleration is 0 ms^-2 , which clearly indicates that the force is 0 newtons, so therefore the only acceleration that exist is gravitational acceleration