Answer:
The 1470 kJ of energy supplied by the yogurt would be consumed by 150 W of work (efficiency of 20%) in about 32.7 h. Then if people is not careful, easily would have more energy from the food that the amount that can consume exercising.
Explanation:
Step 1.
- Energy supplied: 1470 kJ = 1470000 J.
- Rate of energy used for the : 150 W = 150 J/s. <em>This means that each second of this kind of work requieres 150 J of energy,</em>
Step 2
For this case, efficiency is defined as the relationship between the actual rate of energy used, to the rate of energy consumed to obtain it. So:

Then the rate of energy required for this work, is calculated solving for
:

<em>This means that for a work that as a rate of 150 J/s , It requieres to consume energy at a rate of 750 J/s.</em>
Step 3
Now, it is possible to calculate how much time would be needed to consume the 1470000 J of energy of the yogurt. It done using this relationship:

Where Energy stands for the total amount of energy that would be consumed, and rate stans for the rate of energy consumption, Then the time would be:

Then if for the consumption of 1470 kJ of energy is required almost 33 hours, Then is easy to see that the amount of enegy that can be obtain of food would much more than the amount that can be depleted by exercise
Answer:
The answer to your question is below
Explanation:
To explain what happens with the ball we must remember the Law of Conservation of Energy.
This law states that the energy can be neither created nor destroyed only converted from one form of energy to another.
Then,
At the top of the hill, the potential energy is maximum and the kinetic energy equals to zero.
When the ball starts to roll down the potential energy will be lower and the kinetic energy will have a low value.
At the middle of the hill, both energies have the same values.
At the end of the hill, the potential energy will be equal to zero and the kinetic energy will be maximum.
<span>The visible light has wavelength in the range 400 - 700 nano-meters. The wavelengths longer than visible light are: 1-Infrared waves (used in ringtone/mobile waves)2-microwaves - used to heat and cook food. 3- Radio waves - used in communication purposes.</span>