Based on how they each acted in the trials, the substance that would be the most metallic is B.
<u>Answers
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1) B. longitudinal.
2) B. air is cooler than the ground.
<u>Explanation
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Q1
There are two categories of a wave. That is transverse and longitudinal waves. Transverse waves forms crests and troughs while longitudinal forms compressions and rarefaction as they travel. Rarefactions are regions where the wavelengths are longer than other regions.
Q2
As the ray of light moves from an optically less dense to a more dense region it bends towards the normal.
If the sound is bending away from the earth's surface, then the ground must be warmer than the air. As the sound travels it moves from optically dense medium to a less dense medium. For this reason it bends away from the normal. This can only happen when, B. air is cooler than the ground.
If two people hit identical tennis balls at the same time, the ball that has the most kinetic energy is the ball that moves at the fastest speed.
<u>Explanation:</u>
The energy possessed by an object by virtue of its motion is called its kinetic energy indicating that only moving objects have kinetic energy. The kinetic energy of an object depends on its speed and mass.
It is given by the expression

where m denotes the mass of the object and v denotes its velocity.
since kinetic energy is directly proportional to the square of the velocity, the kinetic energy of an object increases with its velocity.
Hence an object that moves at the fastest speed will have the most kinetic energy.
Now for this problem, what is given is a 40 Newtons which would represent the force to be applied to the object, and a distance of 10 meters after the application of the said force. When these two combine, work is done. The unit for work is Joules and this is what we are looking for. The formula to get Joules or for work would be the force applied to the object multiplied by the distance that it travelled after the application of the force. It looks like this
work = force x distance
Joules = Newtons x meter
so let us substitute the variables to their corresponding places
Joules = 40 N x 10 m
Joules = 400 J
So the answer to this question would be C. 400 J
Answer:
False
Explanation:
Potential energy is stored energy, so it is not in motion. Kinetic energy is the energy in motion.