Friction is any force that opposes another force, like the force of gravity on a rocket or the tread of a shoe on a court. Without friction a swimmer would not move through the water when they pull/kick. Friction also keeps their togs on :D

Temperature does not affect the bounce of a rubber ball. Let's say you bounce a rubber ball on the grass. The result will be different then bouncing a rubber ball on a concrete surface. The result is different because you are using a solid, hard surface to bounce the ball with. But the temperature will not affect the bounce of a rubber ball. you can test it out for youself.

In tenpin bowling, the circumference may not exceed 2 foot, 3 inches. The weight is dependant on the bowler. It ranges from 6 to 16 pounds. I imagine factoring in youth bowlers and male/female adult bowlers, the average weight is between 12-14 pounds. Most adult male bowlers bowl with a 16 pound bowling ball.

Gymnasts put chalk on their hands, and occasionally their feet when competing on the balance beam, to keep their hands from slipping off the apparatus from the sweat. Particularly when competing on the bars, your hands get sweaty from the constant friction and long lasting contact with the bar.

Math and physics go with tennis and most other sports, because of the geometric angles used, along with calculations of wind speeds, type of court surface, environment, ball pressure, string tension, et al. While a player may not explicitly use math or physics, he/she is constantly adjusting to these conditions. It would also be nearly impossible for spectators to enjoy the slow motion or instant replay of tennis shots, were it not for the use of math and physics.

The word intensity as it applies to Prilepin's chart for determining the optimal weight for reps and sets, is one thing, but I will assume you are asking what is the effect on your central nervous system if you perform an exercise faster. If you train faster with an increased speed, you will become faster in that exercise. Training slow makes you slow. There are those who say that as long as you train to failure, you will be activating the fast twitch muscle fibers and so you do not have to train so fast but most strength athletes use some type of speed training.

It must be noted that for speed strength training to have any great effect on your athleticism, you should be fairly strong first. Lift heavy things first and then work on your speed. This seems to be the best protocol.

Speed can be a factor in many ways in basketball. On offense, it can help you get passed the defender. On defense, it can hep you get in position to block shots or steal the ball. When a team is faster overall, it enables many fast break opportunities for easy scores.

This has actually been tested on the "Mythbusters" television program, only with American footballs. The answer is that it really doesn't matter much because the weight of the ball and air resistance include forces that far exceed the difference that air density versus helium density might cause.

== == The proper air pressure in an NBA basketball is around 7 1/12 to 8 1/2 lbs.

Yes, friction CAN be harmful, depending on where it occurs.

If you'd fall and scrub your knee, that's harmful friction.

IF your shoes are chafing and yopu get a blister, that's harmful friction.

In a machine, if a bearing becomes warm, that's harmful friction.

Skydivers do NOT move upwards at all when we open our parachutes. We don't even bounce a little. That is an illusion caused by the camera operator still falling at full speed while the first jumper opens their parachute and slows.

Now, it is possible to move upwards in some limited circumstances. When exiting a fast-moving aircraft while wearing a wingsuit, you can rise above the plane for a (very) short time. Also, once your parachute is open, you can flare your canopy enough to slightly (by a few feet) gain altitude.

There are 2 types of parachute - the round parachute and the more modern wing parachute. The round parachute is a decelerator and works on drag only through the atmosphere. However, with the wing shaped 'square' parachute, they act with an additional force of lift. Another name for this type of parachute is the Ram Air Parachute.

Whilst few of them ever generate enough lift to gain altitude, they do create masses of forward motion which gives them better range to land back on the dropzone. You also get better, safer landings which are easier on the knees! Most dropzones these days only use squares.

I would recommend a tandem jump for your first one which uses this more modern type of parachute.

A parachute is deployed using a smaller drogue pilot chute which drags the main parachute off the container. The container is a combined harness which holds the packed parachute on your back. As the parachute inflates, it will slow you down from 120mph to around 10mph average. The final stage is landing, where the skydiver pulls down on both steering toggles to further slow down the decent rate for a tip-toe soft landing.

It makes the air inside expand and will stretch the plastic and make the ball bigger. If you keep heating, the ball will split and let the air out.

I once tried to fix a ball that was pushed in and so had a dent by boiling it until the dent popped out. The dent did pop out, but the ball was bigger than it was and did not bounce like it should-- maybe a child could get some use from it, but to me, it was useless.

Because while a larger mass has a proportionally greater inertia (resistance to movement) than a smaller one, the pull of gravity also affects it that much more. The net result is to exactly cancel out the forces, allowing all objects within a given gravitational field (regardless of their mass) to fall at the same rate... unless there's another force, like air resistance on a feather, to tip the balance.

Spalding NEverflat Matchplay. Incredibly durable. best investment for drill or games. Its developed from breakthrough technology so your soccer ball stays inflated longer than traditional soccer balls.

The furthest a soccer ball has been kicked is 80 meters or 262.46 feet!!!

The average speed of a kicked soccer ball depends on the age and fitness of the kicker. For youth players, the average speed is 15 meters per second, while professional soccer players average 30 meters per second. Adult non-professional soccer players average speeds of 25 meters per second.

No. he is a fictional character for only entertainment purposes

Both liquid and gas

my soccer coach (....... Ferguson) can kick it around 79 MPH NO 79MPH is definitely fast but in Seria A, Ibrahimovic of Inter scored a whooping goal 128mph

Hami Mandıralı - Turkey - San Marino (1996) - 266 km/h

A counter attack is a move that happens when one's opponent is on the attack. When one's opponent is in the process of the attack (signified by the forward movement of the arm holding the blade), the counter attacker will attack into his opponent's attack. Essentially, the counter attack is a move that either stems out of a lack on the fencer's part to use another move, or an attempt to hit their opponent before they themselves can be hit. A counter attack can only be called as such if the other fencer has already begun their attack.

normal air. However since many footballs are produced in cities like Beijing, where there is a lot of pollution, the air may not be as "clean" as the air in the West

Hot.

Personal experiments have shown that temperatures below 25°C make the ball bounce less. From 25°C and upwards there aren't any greater changes in height of bounce. The balls bounce almost the same.