Answer:
If the rifle is held loosely away from the shoulder, the recoil velocity will be of -8.5 m/s, and the kinetic energy the rifle gains will be 81.28 J.
Explanation:
By momentum conservation, <em>and given the bullit and the recoil are in a straight line</em>, the momentum analysis will be <em>unidimentional</em>. As the initial momentum is equal to zero (the masses are at rest), we have that the final momentum equals zero, so
now we clear 
and use the given data to get that
<em>But we have to keep in mind that the bullit accelerate from rest to a speed of 425 m/s</em>, then <u>if the rifle were against the shoulder, the recoil velocity would be a fraction of the result obtained</u>, but, as the gun is a few centimeters away from the shoulder, it is assumed that the bullit get to its final velocity, so the kick of the gun, gets to its final velocity 
too.
Finally, using we calculate the kinetic energy as
North-East
If the wins makes it to east, then the motor goes north Then it would go North-East
Only Condition for Resonance is-
It occurs when the first object is vibrating at the natural frequency of the second object. It always result into a big vibration/loud sound.
Resonance is process by which a vibrating system or an external force drives another system to oscillate with greater frequencies at specific frequencies called resonant frequencies. At resonance frequencies, small periodic driving forces have capacity to produce large amplitude oscillation.
∴ In given scenarios, the case which accurately describes a condition in which resonance can occur is-
C. A pipe's length is equal to 1⁄2 of the wavelength of the sound waves produced by a tuning fork vibrating over one end of the pipe that's open to the air at both ends.
