Underhand serve is a type of volleyball serve in which a player holds the ball with one hand and swings the other hand in an arc motion, striking under the ball with a fist to put it into play. An underhand serve is the most common serve for beginners.
When you know both the speed and direction of an object’s motion, you know the velocity of an object. speed in a given direction is called velocity
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Answer:
The experimental scientist
Answer:
Time period between the successive beats will be 0.1703 sec
Explanation:
We have given speed of the sound v = 349 m/sec
Wavelength of piano 
Wavelength of piano 
So frequency of piano A 
Frequency of piano B 
So beat frequency f = 455.61 - 449.74 = 5.87 Hz
So time period 
So time period between the successive beats will be 0.1703 sec