A proton initially has V = (-5.60)î + (-15.0)ĵ + (4.20)k and then 2.20 s later has V = (-2.90)i + (-15.0)j + (-6.30)k (in meters per second). (a) For that 2.20 s, what is the proton's average acceleration a avg in unit vector notation, (b) in magnitude, and (c) the angle between á avg and the positive direction of the x axis?

Frequency of the vibration due to crevice is 1500 Hz.

Explanation:

Frequency is defined as rate of vibration per second. Its S.I. unit is s⁻¹ or Hz.

According to the problem, we have to find number of crevice car makes in 1 second.

Speed of car, u = 30 m/s

Distance covered by car in 1 second, d = 30 m

For every 0.02 m, one crevice occurred by the tire of car.  

Number of crevice occurred in 1 second by the car =  

                                                                                    = 1500

Since, each crevice makes a single vibration. Thus, the frequency of these vibrations is 1500 Hz.