It is true that a physical change occurs when a material changes shape or size, but the composition of the material does not change. The correct answer is True.
Answer: Physical
Explanation: There are no changes being done to the salt. Think of it this way, if you dissolve the salt in water then boil the water completely, you will have the same salt you started with.
Answer:
The girl has greater tangential acceleration
Explanation:
The angular acceleration (
) of the merry go round is equal to the rate of the change of the angular velocity,
:

Since all the points of the merry go round complete 1 circle in the same time, the angular velocity of each point of the merry go round is the same, and so all the points also have the same angular acceleration.
The tangential acceleration instead is given by

where
is the angular acceleration
r is the distance from the centre of the merry go round
Since the girl is near the outer edge and the boy is closer to the centre, the value of r for the girl is larger than for the boy, so the girl has greater tangential acceleration.
The wavelengths of the light are 4.3 * 10^-12 m and 0.2 m respectively.
<h3>What is wavelength?</h3>
The term wavelength has to do with the horizontal distance that is covered by a wave. We know that a long wavelength implies that the wave is able to travel a long distance from one point to another.
Given that;
c = λf
c = speed of light
λ = wavelength of ight
f = frequency of light
Thus;
λ = 3 * 10^8/ 7.00 x 10^19
λ = 4.3 * 10^-12 m
λ = 3 * 10^8/1.50 x 10^9
λ = 2 * 10^-1 or 0.2 m
Learn more about wavelength:brainly.com/question/13533093
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Missing parts:
What are the wavelengths of electromagnetic wave in free space that have the following frequencies? (a) 7.00 x 10^19 Hz______ pm (b) 1.50 x 10^9 Hz__________ cm