Answer:
The condition necessary for the person to be able to remain stationary in mid-air is that there must be an upward force also referred to as THRUST
Explanation:
Thrust in Physics is defined as the force that propels, forces or pushes the mass of a certain object in a specified or particular direction.
Thrust can defined in the terms of a Jet pack can be defined as the force that is required to propel the mass of a person in an upward direction.
Based on the diagram that we have been shown the question, we can see that water is the fuel used to proper the user or person upwards hence, the jet pack used in the question is an HydroJet pack
The condition necessary for the person to be able to remain stationary in mid-air is that the propelling force called the thrust must be upwards such that it can overcome these 4 things:
a) Gravitational force
b) Mass of the jet pack user
c) Mass of the jet pack itself
d) The water which serves as fuel for the jet pack.
Answer:
(a) To draw water from a well we have to pull at the rope.
(b) A charged body attracts an uncharged body towards it.
(c) To move a loaded trolley we have to pull it.
(d) The north pole of a magnet repels the north pole of another magnet.
Explanation:
Just trust me
Answer:
Acceleration will be 
Explanation:
We have given initial speed of the car is 70 km/hr
We know that 1 km = 1000 m
And 1 hour = 3600 sec
So 
It is given that car stops in 12 sec
So final speed of the car v = 0 m/sec
Time t = 12 sec
From first equation of motion v = u+at
So 
( negative sign indicates that speed of the car will constantly decrease )