Answer:
D-it's never acceptable to ignore rules and etiquette
Explanation:
<h2>
Kinetic energy just before hitting the floor is 324.57 J</h2>
Explanation:
Weight of volleyball player = 650 N
That is
Mass x Acceleration due to gravity = 650
Mass x 9.81 = 650
Mass = 66.26 kg
We also have equation of motion v² = u² + 2as
Initial velocity, u = 0 m/s
Acceleration, a = 9.81 m/s²
Final velocity, v = ?
Displacement, s = 0.5 m
Substituting
v² = u² + 2as
v² = 0² + 2 x 9.81 x 0.5
v = 3.13 m/s
Velocity with which he lands on ground is 3.13 m/s
We have kinetic energy = 0.5 x Mass x Velocity²
Substituting
Kinetic energy = 0.5 x 66.26 x 3.13²
Kinetic energy = 324.57 J
Kinetic energy just before hitting the floor is 324.57 J
Answer : The frequency decreases by a factor of 2.
Explanation :
Given that the wave travels at a constant speed. The speed of the wave is given as :
Where
υ is the frequency of the wave
and λ is the wavelength of the wave.
In this case, the speed is constant. So, the relation between the frequency and the wavelength is inverse.
If the wavelength increases by a factor of 2, its frequency will decrease by a factor of 2.
Hence, the correct option is (A) " The frequency decreases by a factor of 2 ".
The correct answer is
<span>B. if Earth rotated on an axis that was not tilted with respect to Earth's orbit
In fact, the fact that Earth's axis is tilted is the reason why the durations of day and night are different in every part of the Earth. If the axis was not tilted, we would have exactly 12 hours of day and night in every point of the Earth, for the whole year.</span>
