It’s Friday night bowling with your friends, but when you get there, you see they’ve invited him. Your nemesis. The guy who always gets picked for the team before you. Sure, he’s a geek with that monogrammed bowling shirt, but he can bowl. So, what does he know that you don’t? Probably something about the physics of bowling. Now you can too.
Ball Velocity – Faster is Better
If you want a good chance of getting a strike, you’ll need to maximize the ball’s velocity. The wind up determines the amount of velocity, and kinetic energy, that will be imparted to the ball.
Did you know? Friction is the resistance that occurs when one object is moved in contact with another. The resistance between the bowling ball and the lane causes the ball to slow down as it rolls towards the pins. Bowling alleys apply oil to the lanes to reduce friction.
Bowlers typically start with the ball at waist-level and then raise it upwards and behind them as they walk, skip, or shimmy towards the foul line. The raising of the ball creates potential energy between the height that it is lifted and the height of its release. As the ball is released, the potential energy is converted to kinetic energy. The approach to the foul line steadies the bowler, but adds little to the ball’s velocity and kinetic energy.
Another factor in maximizing the ball’s velocity is how high off the ground the ball is released. Good bowlers release the ball as close to the ground as possible, usually between 7.5 and 10 cm, so that the force exerted on it is parallel to the horizon. Dropping the ball from say, 25 cm, not only makes a loud crack that will cause other bowlers to turn and stare, but it adds bounce. The bounce results in vertical velocity, which reduces the horizontal velocity and slows the ball down. It’s almost better to use both arms to roll the ball from between your legs than to drop it!
How to Get Some “Pin Action”
Did you know? In an elastic collision, the total kinetic energy of all the objects remains the same both before and after the collisions occur.
Once you’ve thrown the ball down the lane with all your might, cross your fingers and hope for some good “pin action”. “Pin action” is the activity of the pins bumping into each other after the ball has hit them. The ball transfers its kinetic energy to the pins and they knock against each other in a series of elastic collisions. Hitting the “pocket” is the most efficient way for the ball to transfer its kinetic energy to the pins and creates good “pin action”. For a right-handed bowler, the “pocket” is between pins 1 and 3; for a lefty, it is between pins 1 and 2. A ball hitting the “pocket” increases the chance of all the pins being hit hard enough to overcome their inertia, causing them to fall down.
So what’s going on when the pins wobble but don’t fall over? That means that the ball was not able to transfer enough energy to disturb the centre of gravity of the pins.
Did you know? A perfect hook ball only hits four of the pins. It hits the “pocket” and rolls through to hit the 5 pin and then the 9 pin. The other pins will be knocked down by collisions with these pins.
The Hook Ball
If you really want to kick some butt, you’ll want to throw a hook ball instead of a ball that rolls straight down the lane. Hook balls glide about 2/3 of the way down the lane and then curve toward the pins.
Bowling alleys only apply oil to the first 2/3 of the lane. Therefore, a ball thrown with side spin can take advantage of the sudden increase in friction when it reaches the un-oiled portion of the lane and will be propelled towards the “pocket”.
Now that you know the secrets, it’s time to get out there and bowl! With physics on your side, and a little luck of course, you’ll be sure to hear the sweet sounds of strikes in no time.
“The Physics of Bowling” by Craig Stephenson
“The Physics of Bowling” from topendsports.com
MadSci Network: Physics - Re: Could you please explain the physics of bowling?
“The Physics of…Bowling” from mrfizzix.com
Saunders, F. (2000) The Physics of …Bowling. It takes a good machine to really get a handle on axis, rotation, friction, inertia, speed, and spin. Discover magazine, March, 2000. Available at http://discovermagazine.com/2000/mar/featphysics
Hopkins, D.C. and J.D. Patterson (1977) Bowling frames: Paths of a bowling ball. American Journal of Physics 45: 263-266