Questions

The ball with which Table Tennis is played is called Ping Pong Ball.

According to the International rules, the diameter of the ping pong ball must be not less than 39.5 millimeters and not greater than 40.5  millimeters having a mass of 2.7 grams.

Brooks Koepka shot a final round 68 for 281 (+1) to win his second straight U.S. Open, one stroke ahead of runner-up Tommy Fleetwood, who closed with the sixth round of 63 in U.S. Open history.

It will stop at a height where the weight of the balloon with contents is equal to the weight of air displaced by it, i.e , when the upthrust is equal to the downthrust. The question of bursting will depend on how much difference of pressure inside and outside , the material of the balloon can withstand. It is assumed the balloon is filled with a lighter than air gas like hydrogen or helium.

The resistance of metallic conductors e.g, platinum, increases with rise of  temperature . The increase in temperature results in a decrease of current which can be recorded in a galvanometer if the conductor is included in an electrical circuit. Thus the temperature can be known; platinum resistance thermometer is used generally for accurate scientific work. When two dissimilar metals are joined at the ends, and these ends are subjected to a difference of temperature, a current flows through the metals. Greater the difference of temperature , greater the current. So the curent strength can form the basis for measuring the difference in temperature. And when one of these temperatures is known, we can calculate the other.