100-150 words. Again, for each post you should provide student original writing and cite your source in text as well as provide full end ref information in APA format.
It is easier for a person to float in the ocean than in an ordinary swimming pool. This is because the salt in the ocean water adds to the mass of the water. This in turn makes the water denser than the water in a swimming pool, which does not contain salt and is therefore less dense because it has less mass. The denser the water, the better the ability to float. We can also add to this the concept of buoyant force, which is “the upward force exerted by a fluid on a substance partly or completely immersed in it” (Ostdiek & Bord, p. 148). Using our understanding of buoyant force, we can deduct that the water in the ocean is going to create a stronger upward force than the swimming pool water. Since the buoyant force of either type of water is greater than the weight of the person, the person will float, but they would float higher or better in the saltwater.
Consider a potato being cooked in a conventional oven; it will cook faster if a large nail is inserted into it. Based on what I have learned about conduction, which is “the transfer of heat by direct contact between atoms and molecules” (Ostdiek & Bord, p. 183), the nail will heat up, thereby transferring the heat into the potato and cooking it faster than if it were just being heated from the outside in.
There are three methods of heat transfer: “conduction, which is the transfer of heat between atoms and molecules in direct contact; convection, which is the transfer of heat by buoyant mixing in a fluid; and radiation, which is the transfer of heat by way of electromagnetic waves” (Ostdiek & Bord, p. 183). When I think of conduction, I think of how after I pour hot coffee into a mug, the mug becomes warm. The heat from the coffee is transferring directly to the mug. Convection is different from conduction because it deals with the heat of a fluid rising. I think of my coffee mug again, and the steam that rises from the fluid when it’s hot. Radiation is different from both conduction and convection because it deals with waves instead of molecules, such as the heat of the sun radiating to earth (Ostdiek & Bord, p. 185).
Ostdiek, Vern J., and Donald J. Bord. Inquiry into Physics. 8th ed., Cengage Learning, 2018.