Answer:
Explanation:
Given that height of the projectile as a function of time is
here we know that
h = 147 ft
so from above equation
now by solving above quadratic equation we know that
<u>Answer</u>:
(B) A pot being heated by an electric burner
(D) A radiator that emits warm air and draws in cool air
(E) A hot air balloon rising and falling in the atmosphere
These are some of the examples of the convection currents.
<u>Explanation</u>:
Earlier, electrons were believed to have positive charges and then electric current were discovered. But later after the invention of electric current and current which is termed to be the flow of electrons and is usually flows from negative to positive terminal. But its convention is not discarded in which current moves from positive terminal to negative and it is called convention current. The direction of current shown in the circuit is said to be the convention current.
Hence, the following are the examples of convention current.
1. Boiling water - The energy travels into the pot from the burner, boiling down the water. Then this warm water is accumulating on the top and colder one is heading down to absorb it, triggering a circular motion.
2. Radiator - Place hot air at the peak and pull cool air at the bottom.
3. Hot air balloon - The air is warmed up by a heating element within the balloon, so the air jumps upwards. This induces the balloon to increase in size due to the inside trapping of the warm air. He removes a few of the warm air when the pilot commences to dive, and cold air takes place, enabling the parachute to drop.
Answer:
42cm
Explanation:
To find the volume of a box, you simply multiply the length, by the width, then by the heigh!
2cm x 7cm x 3cm = 42cm
I hope my answer helped you! :)
Answer:
The statement that refers to convection is Warm air rises and takes heat with it; eventually it cools and sinks
Explanation:
There are in general three modes of heat transfer: conduction, convection and radiation.
- In conduction, the heat transfers through contact
- In convection, the heat transfers through density difference
- In radiation, the heat transfers through wave motion
Consider first statement, 'Land and ocean absorb and re-emit heat from the sun'. Radiation is the only mode of heat transfer where there is no requirement for medium. The heat from sun to land and ocean has traveled by radiation. The process of re-emission also occurs in the same way.
Similarly in second statement the energy reflected of earth's atmosphere traveled by radiation and the last statement where sunlight travels through space without aid of fluids or solids refers to the process of radiation.
In third statement the warm air being less dense rises and takes heat with it; eventually it cools and thereby density increases which causes to sink. Here the movement of air is due to density difference, which concludes that this statement refers to convection