Physics

posted by .

A hot-air balloon is accelerating upward under the influence of two forces, its weight and the buoyant force. For simplicity, consider the weight to be only that of the hot air within the balloon, thus ignoring the balloon fabric and the basket. The hot air inside the balloon has a density of ñhot air = 0.93 kg/m3, and the density of the cool air outside is ñcool air = 1.29 kg/m3. What is the acceleration of the rising balloon?

  • Physics -

    Ignore mass of balloon and basket.

    Consider 1 m^3 of hot air:
    mass, m = 0.93 kg
    net upward force, F
    =(1.29-0.93)=0.36 kg
    = 9.81*0.36 N
    =3.53 N
    acceleration
    = F/m
    = 3.53/0.93 m/s²
    = 3.8 m/s²

    Note: At this acceleration, air resistance is significant.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. physics

    a hot air balloon rise above the ground, accelerating upwards at a rate of 2 m/s^2. The total mass of the hot air balloon and it occupants is 400kg. the density of the air is 1.3 kg/m^3. a) Determine the volume if the hot air balloon. …
  2. PHYSICS

    Several people are riding in a hot-air balloon. The combined mass of the people and balloon is 308 kg. The balloon is motionless in the air, because the downward-acting weight of the people and balloon is balanced by an upward-acting …
  3. physics

    Several people are riding in a hot-air balloon. The combined mass of the people and balloon is 310 kg. The balloon is motionless in the air, because the downward-acting weight of the people and balloon is balanced by an upward-acting …
  4. physics

    On a perfect fall day, you are hovering at low altitude in a hot-air balloon, accelerated neither upward nor downward. The total weight of the balloon, including its load and the hot air in it, is 24000 N. Find the weight of the displaced …
  5. physics

    Several people are riding in a hot-air balloon. The combined mass of the people and balloon is 328 kg. The balloon is motionless in the air, because the downward-acting weight of the people and balloon is balanced by an upward-acting …
  6. Physics

    A hot-air balloon is accelerating upward under the influence of two forces, its weight and the buoyant force. For simplicity, consider the weight to be only that of the hot air within the balloon, thus ignoring the balloon fabric and …
  7. physics

    Several people are riding in a hot-air balloon. The combined mass of the people and balloon is 284 kg. The balloon is motionless in the air, because the downward-acting weight of the people and balloon is balanced by an upward-acting …
  8. physics, math

    A hot air balloon with a mass of 18.0 kg is accelerating upward at 1.80 m/s^2 (Anet = 1.80 m/s^2). What is the weight and buoyant force acting on the balloon?
  9. Chemistry

    A hot air balloon is filled with hot air and the hot air forces the volume of the balloon to expand until the density of the gas in the balloon is less than the density of the outside air. The volume must be 20% larger than the balloon …
  10. chemistry

    A hot air balloon is filled with hot air and the hot air forces the volume of the balloon to expand until the density of the gas in the balloon is less than the density of the outside air. The volume must be 20% larger than the balloon …

More Similar Questions