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the answer is A.
Answer:
The railroad tracks are 13 m above the windshield (12 m without intermediate rounding).
Explanation:
First, let´s calculate the time it took the driver to travel the 27 m to the point of impact.
The equation for the position of the car is:
x = v · t
Where
x = position at time t
v = velocity
t = time
x = v · t
27 m = 17 m/s · t
27 m / 17 m/s = t
t = 1.6 s
Now let´s calculate the distance traveled by the bolt in that time. Let´s place the origin of the frame of reference at the height of the windshield:
The position of the bolt will be:
y = y0 + 1/2 · g · t²
Where
y = height of the bolt at time t
y0 = initial height of the bolt
g = acceleration due to gravity
t = time
Since the origin of the frame of reference is located at the windshield, at time 1.6 s the height of the bolt will be 0 m (impact on the windshield). Then, we can calculate the initial height of the bolt which is the height of the railroad tracks above the windshield:
y = y0 + 1/2 · g · t²
0 = y0 -1/2 · 9.8 m/s² · (1.6 s)²
y0 = 13 m
Answer:
If one charged object is positive, and the other charged object is negative, then the two objects will attract each other. If both objects are positive, the objects will repeal each other. If both objects are negative, the objects will also repeal each other.
The side of this cube will be 2.9996 cm. The net force on the solid cube is acting upward.
What is buoyancy force?
A fluid exerts an upward force against the weight of a partly or completely submerged item. The weight of the overlying fluid causes pressure to rise with depth in a column of fluid.
Given data;
Actual weight.W=0.714 N
Apparent weight,W'=0.450 N
The density of water,ρ=1000 kg/m³
The net force on the solid cube is;
Apparent weight = actual weight - buoyancy force
Buoyancy force = Actual weight - apparent weight
F=W-W'
F = 0.714 - 0.450
F= 0.264 N
The buoyancy force(F) is found as;
F = ρgV
0.264 = 1000 × 9.81 × V
V=2.69 × 10⁺⁵
The volume of a cube is found as;
V=a³
2.69 × 10⁺⁵ m³=a³
a=0.02996 m
As we know that 1 m = 100 cm
a=2.996 cm
Hence, the side of this cube will be 2.9996 cm.
To learn more about the buoyancy force refer to the link;
brainly.com/question/132673
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