We know that speed is a scalar unit while velocity is a vector. The signs are mostly concerned with the magnitude that the car should travel in, the direction is not as important.
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Answer:
A). 1.9 cm
Explanation:
m = Mass of brick = 12 kg
g = Acceleration due to gravity = 9.81 m/s²
r = Radius of hose
A = Area = 
F = Force = 
Let us assume that the pressure required to lift the brick would be atmospheric pressure

The radius of the hose should be 1.9 cm
Density is the best property to use, as while multiple different metals could create cubes with the same color, mass, or volume, no different metal could create a cube with the same mass and volume. Density is based on mass and volume, and as a result no two different metals will have the same density.
Gravity is affected by mass and distance
Answer:
Explanation:
The fish is initially at rest and it is also at rest when the spring is fully stretched at the maximum distance.
Change in gravity potential energy = change in spring potential energy
mgh = 1/2kh^2
Assume gravity constant g is 10m/s^2
2.6*10*h = 1/2*200*h^2
100h^2 - 26h = 0
2h(50h - 13) = 0
h = 0 or h = 13/50 = 0.65m
h = 0 is before the spring is stretched
So the maximum distance is 0.65m.