Passengers in an aircraft are subject to the Normal and Gravity Force acting on them at a low 'orbit', so tiny that it can be many times compared to the same surface of the earth when speaking in general terms.
In a high orbit space vehicle or in the same space, said force decreases considerably or simply disappears, generating the sensation of weightlessness.
Remember that the Force of Gravity is given under the principle

Where,
G = Gravitational Universal constant
M = Mass of the planet
m = mass of the object
r = Distance from center of the planet
When the radius grows considerably the gravitational force begins to decrease.
Answer:
Second Choice.
Explanation:
Jack's Power = W/t
Jill's Power = 2W/(0.5)*t
2/0.5 = 4
Jill's Power = 4*W/t
Jill's Power is 4 times greater than Jack's
Second Choice
Sound waves are longitudal waves meaning they go back and forth
Answer:
W = 9.6 N
Explanation:
Given that,
Area on 1 foot, A = 0.6 m²
Pressure, P = 16 Pa
The pressure is given by force acting per unit area. So,

So, the required weight is 9.6 N.
Answer:
a=0 v = v₀ + a t
a=0 line is horizontal
Explanation:
1, In a graph of acceleration vs. time, we have lines, when the line is horizontal it is zero, when the line has a positive slope the increasing accelerations and when the slope is negative the decreasing acceleration
2, speed and relationship of a car is given by
v = v₀ + a t
where vo is the initial velocity, a is the acceleration and tel time
in this case I will calcograph velocity vs. time the constant acceleration is a straight line.
In general from the graph we can find the initial velocity with the cut at that x and the acceleration of the car with the slope