Answer:
Explanation:
a ) For the ray going into syrup , angle of incidence ( i ) is 29.4 and angle of refraction ( r ) is 18.84
Refractive index of syrup = Sin i / Sin r
= Sin 29.4 / Sin 18.84
= 1.51 .
b ) The wavelength of a light is reduced in a medium by the factor of refractive index so
wavelength in the medium
= Wavelength in air / refractive index of the solution
= 632.8 / 1.51
= 419.07 nm .
The frequency remains unchanged . The frequency in the medium will be same as that in air or vacuum.
Frequency in air = Velocity of light in air / wavelength in light
= 3 x 10⁸ / 632.8 x 10⁻⁹
= 4.74 x 10¹⁴ Hz.
Frequency in the medium is same as that in air.
Velocity in the medium
V = velocity in air / refractive index
= 3 x 10⁸ / 1.51
= 1.98 x 10⁸ m /s
Since velocity is a speed and a direction, there are only two ways for you to accelerate: change your speed or change your direction—or change both. If you're not changing your speed and you're not changing your direction, then you simply cannot be accelerating—no matter how fast you're going.
B is your answer (:
I think.
The correct option is <u>D</u>.
Qualitative observations are observations that are made using our senses of sight, hearing, smell, taste and feel. These observations do not involve numbers or measurements of any kind.
The student's observations regarding the squirrel as is mentioned in options A, B and C involve measurements. Therefore these are not qualitative observations.
Option D, however, is made on the basis of sight, where the student observes the squirrel moving in a zigzag manner.
Therefore, of all the three observations, the student's observation that the squirrel ran in a zigzag pattern is the qualitative observation.
Answer:
The correct answer would be "They are opposites because endothermic reactions require energy and exothermic reactions release energy".