D I think I really don’t know
Answer:
<em>The first option best compares both ramps: "It takes less effort to wheel boxes up the 5 m ramp, but the distance is greater"</em>
Explanation:
Power and Work
If an object is being lifted by a vertical distance y, the work done by the agent is the same regardless of the path taken to reach that heigh. But the power could be different since it depends on the time needed to do the work.
The question talks about 'effort' which we'll assume to be the power, since, as noted above, the work is the same by using any of the ramps. The 5 m ramp makes the job easier because the worker has to push less. It's due to the fact that the component of the weight depends on the sine of the angle formed by the ramp with the floor. The larger ramp makes a shorter angle, thus requiring less effort, through a longer distance.
Thus, the first option best compares both ramps:
<em>It takes less effort to wheel boxes up the 5 m ramp, but the distance is greater</em>
Answer:
Refraction
Explanation:
Refraction is a phenomenon typical of light waves. It occurs when a ray of light passes through the interface between two mediums: when doing so, the ray of light changes speed and also changes direction, according to Snell's Law:
where
are the index of refraction of the first and second medium, respectively
are the angle of incidence and refraction, respectively
When white light enters a prism, therefore, it undergoes refraction, and it changes direction.
However, the index of refraction of a material, n, depends also on the wavelength of the light. In particular, the shorter the wavelength, the higher the index of refraction.
This means that as white light enters a prism, the different wavelengths contained in the white light are refracted at different angles: as a result, the 7 colors of light will separate, and that is why we observe the rainbow when white light enters a prism.
Answer:
Speed
Explanation:
- Speed is a scalar quantity that represents the rate of change of distance. It is calculated as
where
d is the distance travelled by the object (regardless of its direction)
t is the time elapsed
The speed is measured in meters per second (m/s). We can also notice that speed is different from velocity: in fact, speed is a scalar quantity (magnitude only), while velocity is a vector quantity (magnitude+direction).
Answer:
a.6373.5 N
b.-3837.6 N
Explanation:
Mass of roller coaster=m=1040 kg
Radius=r=24 ,
a.
Normal force=
According to question
Where
Substitute the values
b.