Wednesday, 20 August 2014

Explain the phenomenon #2

Group answer : 

My answer : Since the red liquid had a higher temperature than the green liquid, the green liquid would gain thermal energy from the red liquid to reach thermal equilibrium, which caused the end product to be a warm liquid.

Explain the phenomenon #1

Group answer : 

My answer : Water is a poor conductor of thermal energy, thus it convects heat slower to the ice cube, causing it not to melt. This is if I assume that the ice cube did not melt. The water only boiled at the top as convection only happens at the place where is receiving direct thermal energy from, hence water at the bottom half would not boil.

Sunday, 17 August 2014

Think 7

Group answer : 

My answer : I assume that the green liquid has a lower temperature than the red liquid, thus is has a higher density than the red liquid, hence it will sink. The green liquid flows faster than the red liquid as it gained thermal energy from the red liquid which caused its molecules to vibrate faster, thus flowing faster. And since the red liquid had a lower density, it would float above the green liquid.

Second discussion.

Think 6

My answer : Metal B should have a greater expansivity than metal A as it expanded more and bended to cover metal A since it could not expand anymore.

Think 5

Group answer :

My answer : We should heat the ring so that the ring would expand as the distance between molecules increases when energy is supplied to them. When the ring expands, part A would naturally expand as well, thus, the ring would be able to pass through.

Think 4

Group answer :

My answer : The metal cup is a better thermal conductor thus the hot water at 70 degree celsius will decrease faster to thermal equilibrium with the cold water as thermal energy is transferred from the hot water to the cold water. Since styrofoam, the material which contains the cold water, is a poor thermal conductor, thermal energy would not be gained from the surroundings easily to the cold water at 5 degree celsius. After both water reach thermal equilibrium, they would stay at that constant temperature.

Think 3

Group answer : 

My answer : The tiles are a better thermal conductor compared to the parquet floor, thus thermal energy is conducted away from the leg faster on the tiles. Hence, the foot on the tiles would feel cold.

Monday, 28 July 2014

Think 2

Group answer : 

My answer : When you come out of the swimming pool, water droplets on your body gain thermal energy from your body and evaporates into the surrounding, thus, you would lose thermal energy and the molecules in your body would move slower due to a cooler temperature and hence, you would feel cold and shiver as there was a sudden drop in temperature instead of a gradual decrease.

Think 1

Group answer : Heat means higher temperature which leads to faster movement of particles of kinetic energy in the body. When you enter an air-conditioned room, you will feel lose heat and the kinetic energy in your particles will slow down, thus feeling cold. The heat will be transferred to the air-conditioned room.

My answer : After work on a hot day, you would feel hotter than usual as thermal energy causes faster movement of the molecules in your body. However, when you enter an air-conditioned room after that! your body would come in contact with molecules which are moving in a slower movement as it is colder inside which slows down the molecules. Thus, thermal energy would be transferred to the room and you would lose thermal energy, thus feeling cold.