High-speed movies reveal that the time interval during which a golf club is in contact with a golf ball is typically 1.0 x 10^-3 s and the speed of the ball when it leaves the club is about 65 m/s. The mass of a golf ball is 0.045 kg. a) Determine the magnitude of the average force exerted by the club on the ball. (Ignore the foce of gravity) b) Why is it reasonable to neglect the force of gravity in this case? c) What kinds of materials (for the club and the ball) help increase this average force? How does the material maximize the average force? --------------------------------- a) I tried to draw a FBD. The only force seems to be working on the golf ball is applied force (since no gravity, and I am assuming no air friction). Does the action and reaction force have anything to do with it? So far, I have m = 0.045 g ; v1 = 65 m/s ; t = 1.0 x 10^-3 s . What formulas do I use? I can only think of v = root of Rg, but the question said ignore gravity. Anyone has any idea how to do this question? b) I dont know :(, cause I dont understand how this works c) If I knew what force is really acting on it, may be I could give it a try, but I am hopeless now :(. I am always used to do my homework, but this time, looks like I am really stuck. I came here as my last resort :(. I am trying to do this question for the last 3 days, but its useless, and its due tommorow :(. Can anyone help me with this? I would really really appreciate it :).. And mods, admins, the owner may be, if you want I can design a skin for this forum...freelance :). I've been working with vBulletin for over 2 years now, and with vBulletin 3 ever since the first beta came out. Two of my sites are powered by vBulletin. I have experience designing skins for both vBulletin 2 and 3, I will present my portfolio if you are interested :).