Answer:
C. Both a and b
Explanation:
Firstly, persons and objects in a moving plane as described in this question, are moving at the same speed as the plane even if there is no individual movement of these objects.
However, this question describes a person sitting still in a moving plane. This means that;
- The person is motionless in relation to everything in the plane i.e the person is not moving even if other things in the plane are.
- The person is in motion compared to everything on the ground i.e. the person is moving at the same speed as the plane, hence, in comparison with the ground, the person is moving.
Therefore, options A and B are correct
Answer: i didnt look at your question its to long
Explanation:
Answer:
vf = v₁/3 + 2v₂/3
Explanation:
Using the law of conservation of linear momentum,
momentum before impact = momentum after impact
So, Mv₁ + 2Mv₂ = 3Mv (since the railroad cars combine) where v₁ = initial velocity of first railroad car, v₂ = initial velocity of the other two coupled railroad cars, and vf = final velocity of the three railroad cars after impact.
Mv₁ + 2Mv₂ = 3Mvf
dividing through by 3M, we have
v₁/3 + 2v₂/3 = vf
vf = v₁/3 + 2v₂/3
The most accurate answer among the choices would be the fourth one, because if the weight of the air displaced is greater than the balloon's weight, the balloon will float upwards. Density of the air also plays a part. Hot air = less dense. Hope my answer has come to your help.
Answer:
v = 306.76 Km/h
Explanation:
given,
height of the aircraft = 3000 m
differential pressure reading = 3300 N/m²
density of air = 0.909 Kg/m³
speed of aircraft = ?
Assuming the air flowing above air craft is in-compressible, irrotational and steady so, we can use Bernoulli's equation to solve the problem.
using Bernoulli's equation

where ρ is the density of the air at 3000 m



v = 85.21 m/s

v = 306.76 Km/h