Which applications, either for diagnostic purposes or for therapeutic purposes, do not involve ionizing radiation? check all that apply. ct scan mri ultrasound laser surgery radiopharmaceuticals pet scan

These applications DO NOT INVOLVE harmful ionizing energy:

- MRI

- ultrasound

- laser surgery

Applications in which ionizing radiation are not used are  

 MRI

ultrasound

 laser surgery

Explanation:

Ionizing radiation

Ionizing radiations are radiation which have sufficien energy to ionize an atom. Example of ionizing radiation are x rays, gamma rays and all particle radiation from radioactive decay

CT Scan

CT scan is an abbreviated form of computerized tomography. CT scan provide more information about a body than x-rays. In this test a sequence of x-ray images are taken at various angle of a body and these images after computer processing  provide information about the body. Since x-ray is ionizing radiation so in CT scan ionizing radiations are used.

Ultrasound

In ultra sound scan high frequency sound waves(which are not ionizing radiation) are used to find the information about a body.

MRI

MRI is an abbreviated form of Magnetic resonance imaging. In MRI scanning high intensity magnetic field and radio waves(which are not ionizing radiation) are used to find the information of a body.

Laser surgery

It is a type of surgery in which laser beam(which are not ionizing radiation) is used to cut the skin or to remove a lesion from skin surface.

Radiopharmaceuticals PET scan

PET scan is an abbreviated form of positron emission tomography scan. This test is used to find the images of a body to detect certain diseases like cancer and heart diseases in your body.  In this test radioactive tracers are used. In this test ionizing radiation are used.

scattering of light by tiny particles in air to produce the colors we see on sky, is dependent on the following factors:

(i) wavelength of light

(ii) size of the scattering particle  

(iii) distance traveled by light through the atmosphere.

according to rayleigh's law of scattering, the amount of scattering is inversely proportional to the fourth power of its wavelength. shorter the wavelength, greater is its scattering. hence violet/blue light is scattered more than red.

sun's light is a composite light ( visible light) with wavelengths in the range 400 nm (violet) to 700 nm (red). as sunlight passes through our atmosphere, the molecules of air scatter light according to their wavelengths. during sunrise and sunset, the sun's position is below the horizon. hence light from the sun travels a greater distance in the atmosphere when compared to its position a noon.

as sunlight enters the earth's atmosphere, blue light is scattered away and at the end of its journey in the sky, only red and orange wavelengths remain in the beam.

hence at sunrise and sunset, the sky appears reddish orange.

i had this question and the answer was 3.15 miles.

martina travels from school to her mom's office. from there, she walks to school. after school, she walks to the library and then to a friends house before finally ending back at home. find martina's total distance traveled.

a) 0 miles  

b) 0.4 miles  

c) 1 mile  

d) 3.15 miles