Negative energy by catching it. Changes the force and movement of the baseball. Loses energy. Kinetic energy
Answer:
Option D
Explanation:
The work done can be given by the mechanical energy used to do work, i.e., Kinetic energy and potential energy provided to do the work.
In all the cases, except option D, the energy provided to do the useful work is not zero and hence work done is not zero.
In option D, the box is being pulled with constant velocity, making the acceleration zero and thus Kinetic energy of the system is zero. Hence work done in this case is zero.
Sound intensity = 1/(r^2)
That is Sound intensity is indirectly proportional to the distance. Therefore, sound becomes 9 times less intense.
Answer:
The frequency of the sound wave is 800Hz
The speed of sound in a is about 340m/s.
Velocity = frequency x wavelength
making wavelength the subject formula
wavelength = Velocity/frequency.
wavelength = 340/800
wavelength = 0.425m.