Answer:
141.78 ft
Explanation:
When speed, u = 44mi/h, minimum stopping distance, s = 44 ft = 0.00833 mi.
Calculating the acceleration using one of Newton's equations of motion:
Note: The negative sign denotes deceleration.
When speed, v = 79mi/h, the acceleration is equal to when it is 44mi/h i.e. -116206.48 mi/h^2
Hence, we can find the minimum stopping distance using:
The minimum stopping distance is 141.78 ft.
The concept to develop this problem is the Law of Malus. Which describes what happens with the light intensity once it passes through a polarized material.
Mathematically this can be expressed as
Where
I = New intensity after pass through the Polarizer
= Original intensity
= Indicates the angle between the axis of the analyzer and the polarization axis of the incident light.
When the light passes perpendicularly through the first polarizer, the light intensity is reduced by half which will cause the intensity to be at the output of the new polarizer, mathematically:
Solving to find the angle we have
The orientation angle of the second polarizer relative to the first one is 43.11°
Answer:
The high of the ramp is 2.81[m]
Explanation:
This is a problem where it applies energy conservation, that is part of the potential energy as it descends the block is transformed into kinetic energy.
If the bottom of the ramp is taken as a potential energy reference point, this point will have a potential energy value equal to zero.
We can find the mass of the box using the kinetic energy and the speed of the box at the bottom of the ramp.
Now applying the energy conservation theorem which tells us that the initial kinetic energy plus the work done and the potential energy is equal to the final kinetic energy of the body, we propose the following equation.
And therefore