Answer:
A
Explanation:
Hooke's law! F(spring)=-kx
There's no tricky square law here. The spring constant doesn't change, only x (distance stretched) changes. Therefore, if distance is halved, Force will be halved.
<span>10 times as much. Since F=m*a, and a is constant, the only thing that affects force is the mass.
In response to the below answer, the acceleration due to gravity does not change. The force due to gravity definitely DOES change depending on the mass of the object. Since the force is what the problem asks for, the answer is 10</span>
When is at the end of the runway the velocity of the plane is given by the equation
where s=1800 m is the runway length. Thus
At half runway the velocity of the plane is
Therefore at midpoint of runway the percentage of takeoff velocity is
‰
Fine, lets do a retry of this.
Δd = -0.9m
v₁ = 0
v₂ = ?
a = -9.8 m/s²
Δt = ?
We can use the following kinematic equation and solve for Δt.
Δd = v₁Δt + 0.5(a)(Δt)²
Δd = 0.5(a)(Δt)²
2Δd = a(Δt)²
√2Δd/a = Δt
√2(-0.9m)/(-9.8 m/s²) = Δt
0.<u>4</u>28571428574048 = Δt
Therefore, it takes 0.4 seconds for the glass to hit the ground, or 0.43s as you said (even though I don't believe it follows significant digit rules)
