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 and Explanation:
The gravitational acceleration 'g' depend directly on the mass of the object or body and inversely on the distance or radius squared:
where
= mass of the object
G = Gravitational constt
Thus the plastic ball is lighter and have low mass as compared to the steel and golf balls.
This is the reason that a plastic ball have a low value of acceleration as compared to that of steel and golf balls with higher values of acceleration.
Evaporation is a process that requires energy to occur endothermic reaction.
Answer:
Brown dwarf has the lowest temperature
Tools we'll need:
Speed of EM wave in vacuum = 3 x 10⁸ meters per second.
Frequency = (speed) / (wavelength)
Period = 1/frequency
Period = (wavelength) / (speed) = (0.15) / (3 x 10⁸) = <u>0.5 nanosecond</u>
( "nano..." = 10⁻⁹ )