the answer is d it reflects all the wavelengths of visible light.
To be honest I don’t know
Answer:
x = 27.3 m
Explanation:
This is a projectile launching exercise, let's start by looking for the time it takes for the rock to reach the height of the window.
Let's use trigonometry to find the velocities of the rock
sin 40 = / v
cos 40 = v₀ₓ / v
v_{oy}= v sin 40
v₀ₓ = v cos 40
v_{oy} = 30 sin 40 = 19.28 m / s
v₀ₓ = v cos 40
v₀ₓ = 30 cos 40 = 22.98 m / s
we look for the time
= v_{oy}^2 - 2 g y
v_{y}^2 = 19.28 2 - 2 9.8 16 = 371.71 - 313.6 = 58.118
v_{y} = 7.623 m / s
we calculate the time
v_{y} = v_{oy} - gt
t = (v_{oy} - v_{y}) / g
t = (19.28 -7.623) / 9.8
t = 1,189 s
since the time is the same for both movements let's use this time to find the horizontal distance
x = v₀ₓ t
x = 22.98 1,189
x = 27.3 m
Answer: C) 48 N forward
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Explanation:
Subtract the two forces, since they are working opposite one another.
79-31 = 48
The net force is 48 newtons forward. The truck is moving forward since the engine's force (79 N) is larger than the force of friction (31 N).
The force of friction cannot exceed the engine's force because friction only slows down an object, and does not push the object backward. In other words, if the object was stationary, then the ground isn't pushing the object backwards assuming you're on a level flat ground.