The force constant of the spring is determined as 14,222.2 N/m.
<h3>Force constant of the spring</h3>
Apply the principle of conservation of energy,
K.E = U
where;
- K.E kinetic energy of the elevator
- U is elastic potential energy of the spring
¹/₂mv² = ¹/₂kx²
mv² = kx²
k = mv²/x²
Where;
- m is mass of the elevator
- v is speed
- x is compression of the spring
k = (2000 x 8²)/(3²)
k = 14,222.2 N/m
Thus, the force constant of the spring is determined as 14,222.2 N/m.
Learn more about force constant here: brainly.com/question/1968517
#SPJ1
Answer:
When the ejected air is moving in the downward direction then the thrust force acts in the upward direction, due to reversal thrust, the jets can take off vertically without needing a runway this way.
Explanation:
Newton’s third law motion states that for every action there will be an equal and opposite reaction.
Thrust reversal is also known as reverse thrust. It acts opposite to the motion of the aircraft by providing the deceleration.
Commercial aircraft moves the ejected air in the forward direction means that the thrust will acts opposite to the motion of the aircraft that is backward direction due to thrust reversal. This thrust force might be used to decelerate the craft.
Uses of thrust reversal in practice:
When the ejected air is moving forward direction then the thrust force moving backward direction due to reversal thrust the speed of the craft slows down.
When the ejected air is moving in the downward direction then the thrust force acts in the upward direction, due to reversal thrust, the jets can take off vertically without needing a runway this way.
42- C
43- A
44- C
45- A
46- B
47- D
Answer:

Explanation:
The equations of equilibrium for the child are: (x' in the direction parallel to slope, y' in the direction perpendicular to slope)

After some algebraic manipulation, an expression for the coefficient of kinetic friction is obtained:





