So we want to know how can we detect infrared rays without an instrument. Infrared rays or heat, are a part of electromagnetic spectrum. We have specialized nerve cells in our skin called thermoreceptors that can detect differences in temperature that are produced by infrared part of EM spectrum.
Answer:
V=14.9 m/s
Explanation:
In order to solve this problem, we are going to use the formulas of parabolic motion.
The velocity X-component of the ball is given by:

The motion on the X axis is a constant velocity motion so:

The whole trajectory of the ball takes 1.48 seconds
We know that:

Knowing the X and Y components of the velocity, we can calculate its magnitude by:

The correct answer to this is (A. Units Only).
It shows that there is a velocity of 35, but the units are missing.
Answer:
Person B
Explanation:
Person B will hear the frequency that is lower than the B- flat.