A transcript of a presidential speech (APEX Class ;)
Answer:
The magnitude of the resistive force exerted by the water is newtons.
Explanation:
By First and Second Newton's Law, the resistive force exerted by the water on the cruise ship has the same magnitude of forward thrust, with which it is antiparallel to. The equation of equilibrium for the luxury liner is:
(Eq. 1)
Where:
- Forward trust, measured in newtons.
- Resistive force exerted by the water, measured in newtons.
From (Eq. 1), we get that: ()
The magnitude of the resistive force exerted by the water is newtons.
To answer this question, it helps enormously if you know
the formula for momentum:
Momentum = (mass) x (speed) .
Looking at the formula, you can see that momentum is directly
proportional to speed. So if speed doubles, so does momentum.
If the car's momentum is 20,000 kg-m/s now, then after its speed
doubles, its momentum has also doubled, to 40,000 kg-m/s.