Question

-After observing all energy demonstrations listed below, write a preliminary working definition of energy.

The energy demonstrations are:

1. beaker of water brought to boil over a hot plate or stove.
2. viscous heat pack (you have all seen them work, you do not have to buy one unless you do not know how they work.
3. popcorn to be popped and eaten (great with your loved one and a movie).
4. battery operated or windup toy car set into motion.
5. children's blocks stacked so that the top block balances precariously.
6. spring-loaded mouse trap (don't get your fingers caught).
7. operating a light bulb
8. walk up and down a flight of stairs a few times (no heart attacks please)
9. turn on a hair dryer.

Answer 1

1 Here what stove is doing is converting chemical energy to heat energy by burning, which is absorbed by water to make them boil, then it is used as transition energy to convert to steam

2. Working of viscous heat pack is the dissipation of mechanical energy in a viscous fluid. Generally, the rate of viscous heat generation depends on the shear rate.

3 we give energy as heat to the cop which is absorbed an molecular changed occur to convert to pop corn, which we eat to change it to glucose which is our source of energy

4. Battery have a stored chemical energy, we use this energy to operate toy car, motor in it convert the chemical energy to the rotation motion, which is connected to tier which helps in motion, in short chemical energy converted to mechanical energy

5. In stalking up of block what we are doing is making sure the centre of mass of the system always remain in centre so that it will be balanced by Gravity.

6 Spring loaded mouse trap: we use our strength to load the spring , in which our energy is converted to potential energy in spring, when mouse step on it the potential energy is converted to Kinetic Energy trapping mouse.

7 the electricity which is got by combustion or nuclear power plant is used to light a bulb by converting electric energy to light, in invadesvend bulb, the electricity heat up the tungston to red hot, which result in light. The electricity is converted to heat and light.

8 Walking up is harder because we are using our energy against gravity as well as friction in ground, but while coming down it would be easy as gravity will act in our support and friction will be always there, so there will be always dissipation of energy

9 in hair dryer the electricity is converted to heat as well as to pump out air, this heat go to the hair, water in hair absorbs this heat and will use as transition energy to evaporate making hairs dry.

"Always Energy is Conserved" or " Energy can neither be created nor be destroyed it can be only changed from one type to another"