A Day at the Beach

Heat transfer project by Daniel Forman

One day, Bob decides to go to the beach to forget about school over the summer. What he didn’t know, was that his ‘trip’ was going to be filled with physics!

As Bob is walking along the sand, it feels very warm. Soon, he starts screaming in pain while his feet are getting burned!

OUCH!

What happens here, is Bob is the victim of Conduction due to the sun’s Radiation. The sun emits its radiation to heat the sand. Since the sand has a low specific heat capacity, it heats fast. When the hot sand comes into

contact with Bob’s foot, heat flows from the sand to his foot, since the sand is a higher temperature than his foot, thus creating a burning sensation.

Bob came to the beach for a big reason -- to swim! So, Bob takes off his sandals, takes off his shirt and goes toward the water to take a swim!

As Bob was swimming, he started to become very cold, and decided to come out of the water. He ran for his towel quickly, before he got too cold.

Here, Bob’s body temperature was higher than that of the water, making it feel cold because it transfers heat back and forth until thermal equilibrium is reached. This is the effect of Conduction.

BRR!

When walking back to the umbrella to get his towel, a breeze of wind blew past him, and he almost fell over! It also gave him the chills!

Explanation

Cool air from convection currents replace the warm air rising from the sand, which is heated from radiation, giving the beach a breeze. This is Convection.

After his chilling swim, he decided to bathe in the sun to get warm, and to get a little rest. He was grabbing for his sun block as he laid down, but fell into a slumber…

Suddenly, Bob awoke, and found it to be getting very late! So he got up from his nap and started to pack his things up. When he was packing, he was feeling some pain in his

whole body. He soon figured out it was because he had become sunburned!!!!!

Bob had laid out in the sun for a long time, without sun block or any other protection. Therefore, radiation from the sun had burned through some of his skin, making it appear pink/red. This is Radiation.

OUCH!OH NO!

So Bob walked down the sidewalk, beside the palm trees. Everything was getting darker by the moment, so he tried to walk a little bit faster toward his home. And so Bob’s day

at the beach was over, and no more heat transfers…or so he thought!

As Bob was walking home he got a phone call. So he set his bag down by a palm tree, and took the call leaning against the tree in the shade. All of a sudden, he became very

chilly, and started shivering! So he said, “Good Bye” and then kept walking home, before it got too dark!

Here, his body is losing temperature from Conduction to the air. The air has a lower temperature, and so it sucks that heat in. He is losing heat also because he isn’t getting that radiation from the sun, which otherwise gives him

heat, which otherwise you would feel the lack of heat.

And so Bob arrived at his house as the sun had come down. He had a long day and now it was time for the day to be over, as well as his Physics lessons in the

summer!