answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Andreyy89
3 months ago
13

A hot air balloon of total mass M (including passengers and luggage) is moving with a downward acceleration of magnitude a. As i

t approaches a mountain, the captain needs to accelerate upwards. He decides to throw enough ballast over board to achieve an upward acceleration of magnitude a/2. What fraction of the initial mass does he have to drop? Assume the upward lift force exerted by the air on the balloon does not change because of the decrease in mass.
Physics
1 answer:
inna [3.1K]3 months ago
5 0

Answer:

The ratio of mass that is discarded is determined by this equation:

M - m = (3a/2)/(g²- (a²/2) - (ag/2))

Explanation:

The force acting on an object in motion is defined by the equation:

F = ma

Additionally, there is a gravitational force consistently acting downwards on the object, defined as g = 9.8 ms⁻²

For convenience, we will utilize a positive notation for downward acceleration and a negative notation for upward acceleration.

Case 1:

The hot air balloon has mass = M

Acceleration = a

Upward thrust from hot air = F = constant

Gravitational force acting downward = Mg

The net force on the balloon can be expressed as:

Ma = Gravitational force - Upward Force                              

Ma = Mg - F                      (since the balloon moves downward, that means Mg > F)

F = Mg - Ma

F = M (g-a)

M = F/(g-a)

Case 2:

After releasing the ballast, the new mass becomes m. The new upward acceleration is -a/2:

The net force is expressed as:

-m(a/2) = mg - F        (The balloon is moving upwards, hence F > mg)

F = mg + m(a/2)

F = m(g + (a/2))

m = F/(g + (a/2))

Determining the fraction of the mass initially dropped:

M-m = \frac{F}{g-a} - \frac{F}{g+\frac{a}{2} }\\M-m = F*[\frac{1}{g-a} - \frac{1}{g+\frac{a}{2} }]\\M-m = F*[\frac{(g+(a/2)) - (g-a)}{(g-a)(g+(a/2))} ]\\M-m = F*[\frac{g+(a/2) - g + a)}{(g-a)(g+(a/2))} ]\\M-m = F*[\frac{(3a/2)}{g^{2}-\frac{a^{2}}{2}-\frac{ag}{2}} ]

You might be interested in
A gas is compressed in a cylinder from a volume of 20.0 l to 2.0 l by a constant pressure of 10.0 atm. calculate the amount of w
Maru [3345]
First, we must transform the pressure into SI units, considering that 1 atm = 1.01 \cdot 10^5 Pa:
p=10.0 atm =1.01 \cdot 10^6 Pa

The starting and ending volumes of the gas will be as follows (keeping in mind that 1.0 L = 0.001 m^3):
V_i = 20.0 L=0.020 m^3
V_f = 2.0 L=0.002 m^3

Thus, the work performed on the gas by its surroundings is
W= -p \Delta V=-p(V_f-V_i)=-(1.01 \cdot 10^6 Pa)(0.002 m^3-0.020 m^3)=18180 J
The positive outcome indicates that this work leads to a rise in the gas's internal energy.
8 0
3 months ago
An organ pipe open at both ends has a radius of 4.0 cm and a length of 6.0 m. what is the frequency (in hz) of the third harmoni
inna [3103]

When air is forced into the open pipe,

L = \frac{nλ}{2}

where n represents any whole number such as 1,2,3,4, etc., and λ denotes the wavelength of the oscillation

This implies λ=\frac{2L} {n}

It is important to note that n=1 corresponds to the fundamental frequency, n=2 corresponds to the first harmonic, and so forth.

Thus, the third harmonic will be for n=4

With L=6m and n=4, solving for λ yields:

λ=\frac{(2)*(6)}{4} =3m

The connection between frequency (f), sound speed (c), and wavelength (λ) is given by:

c=f.λ or f= \frac{c}{λ}

Therefore, f=\frac{344}{3}

≈115 Hz

8 0
2 months ago
Sharks are generally negatively buoyant; the upward buoyant force is less than the weight force. This is one reason sharks tend
Ostrovityanka [3204]
The required lift force is approximately 866.92 N. To determine this, we first establish the shark's mass at 92 kg and its density at 1040 kg/m³. The volume of the shark is calculated by dividing mass by density, yielding 0.08846 m³. The buoyant force acting on the shark is then determined by multiplying the volume by the density of water and gravity, resulting in a lift force of 866.92 N.
4 0
2 months ago
A trained sea lion slides from rest down a long
Keith_Richards [3271]

Answer:

1.5 m/s²

Explanation:

Begin by sketching a free body diagram.  Three forces are at play on the sea lion: the force of gravity acting downwards, the normal force that is perpendicular to the ramp, and the frictional force parallel to the ramp.

Considering the forces perpendicular to the incline:

∑F = ma

N − mg cos θ = 0

This gives us N = mg cos θ

Next, examining the forces parallel to the incline:

∑F = ma

mg sin θ − Nμ = ma

Substituting for N yields:

mg sin θ − (mg cos θ) μ = ma

g sin θ − g cos θ μ = a

hence a = g (sin θ − μ cos θ)

If we set θ = 23° and μ = 0.26:

a = 9.8 (sin 23 − 0.26 cos 23)

this results in a = 1.48

When rounded to two significant figures, the acceleration of the sea lion is 1.5 m/s².

5 0
1 month ago
The equation for the change in the position of a train (measured in units of length) is given by the following expression: x = ½
Keith_Richards [3271]
(B) (length)/(time³) Explanation: The term x = ½ at² + bt³ should meet dimensional consistency. This means that both bt³ and ½ at² must share the same units, which are length. To find the dimension of b, we rearrange the equation: [x] = [b]*[t]³ leads to length = [b]*time³, hence [b] = length/time³.
6 0
2 months ago
Read 2 more answers
Other questions:
  • A 250-kg crate is on a rough ramp, inclined at 30° above the horizontal. The coefficient of kinetic friction between the crate a
    15·2 answers
  • Find the object's speeds v1, v2, and v3 at times t1=2.0s, t2=4.0s, and t3=13s.
    6·2 answers
  • When Jim and Rob ride bicycles, Jim can only accelerate at three-quarters the acceleration of Rob. Both startfrom rest at the bo
    15·1 answer
  • A uniformly charged rod (length = 2.0 m, charge per unit length = 5.0 nc/m) is bent to form one quadrant of a circle. what is th
    15·1 answer
  • A constant-velocity horizontal water jet from a stationary nozzle impinges normally on a vertical flat plate that rides on a nea
    10·1 answer
  • All forces on the bullets cancel so that the net force on a bullet is zero, which means the bullet has zero acceleration and is
    5·2 answers
  • A solid cylinder is radiating power. It has a length that is ten times its radius. It is cut into a number of smaller cylinders,
    10·1 answer
  • Now Abel and Kato use what they learned to answer the following problem. The initial speed of a tennis ball is 54 m/s and the la
    11·1 answer
  • Two stunt drivers drive directly toward each other. At time t=0 the two cars are a distance D apart, car 1 is at rest, and car 2
    8·1 answer
  • Una flecha tiene una rapidez de lanzamiento inicial de 18 m/s. Si debe dar en un blanco a 31 m de distancia, que está a la misma
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!