Answer: D:
A periodic disturbance of a medium
Explanation:
A wave can be Mathematically defined by periodic disturbance of a medium. That is, oscillations of the waves about a fixed position or change in position from the resting equilibrium position. The wave oscillate from equilibrium position with amplitude periodically.
Answer:
this effect is called SCREENING
Explanation:
When a positive charge is surrounded by several negative charges at a long distance, an apparent decrease in the positive charge is observed, this effect is called SCREENING and is noticeable in multielectronic atoms
This effect is responsible for the decrease in ionization energy in the larger atoms.
As we know that range of the projectile motion is defined as
now we know that
horizontal speed =
also in order to find the time of motion we will have
now from the above formula of range we know that
now from above formula we can say that if speed of the ball is twice that of initial speed then the range will increased by 4 times
Answer:
During heat flow, much of the energy is dissipated and cannot be used for useful work.
Explanation:
Which of the following statements is true?
During heat flow, much of the energy is lost.
During heat flow, energy is converted to matter.
During heat flow, much of the energy is dissipated and cannot be used for useful work.
<h2>
Speed of jet is 730 miles per hour and speed of wind is 160 miles per hour.</h2>
Explanation:
Let the speed of jet be j and speed of wind be w.
Flying against the wind a jet travels 1710 miles in 3 hours
Distance = 1710 miles
Time = 3 hours
We have
Distance = Speed x Time
1710 = Speed x 3
j - w = 570 miles per hour ----------------eqn 1
Flying with the wind the same jet travels 6230 miles in 7 hours
Distance = 6230 miles
Time = 7 hours
We have
Distance = Speed x Time
6230 = Speed x 7
j + w = 890 miles per hour ----------------eqn 2
eqn 1 + eqn 2
2 j = 1460
j = 730 mph
Substituting in eqn 2
730 + w = 890
w = 160 mph
Speed of jet is 730 miles per hour and speed of wind is 160 miles per hour.