(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A tennis player hit a serve of 251 km.h^{-1}in a match. Calculate the Drag Force acting on the tennis ball. Diameter of ball is 6.5cm, density of air is 1.3 kg.m^{-3}and air viscosity is 1.8x10^{-5}kg.m^{-1}.s^{-1}.

2. Relevant equations

Drag Force is: Fd= [itex]\pi[/itex].d^{2}.C_{D}.p_{f}.u^{2}.1/4

3. The attempt at a solution

My attempt is to find Reynolds number: Re_{p}= (p_{f}u_{t}d_{p})/u = (1.3)(903,600,000)(0.065)/0.000018

and then use a graph of drag coefficient against Re_{p}to find Cd. However my number for Re is 4.24E+13 which is far too large to be correct. Is there something i am doing wrong?

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# Homework Help: Calculate drag force

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