Maximum generally is 20kHz
beyond 20kHz is considered ultrasound which we cant hear
Answer:
The lines of the magnetic field from a bar magnet form closed lines. By convention, the field direction is taken to be outward from the North pole and into the South pole of the magnet. Permanent magnets can be made from ferromagnetic materials.
As can be visualized with the magnetic field lines, the magnetic field is strongest inside the magnetic material. The strongest external magnetic fields are near the poles. A magnetic north pole will attract the south pole of another magnet, and repel a north pole.
The ability to do work is called energy.
Answer:
A) 100°C
B) 211 g
Explanation:
Heat released by red hot iron to cool to 100°C = 130 x .45 x 645 [ specific heat of iron is .45 J /g/K]
= 37732.5 J
heat required by water to heat up to 100 °C = 85 x 4.2 x 80 = 28560 J
As this heat is less than the heat supplied by iron so equilibrium temperature will be 100 ° C. Let m g of water is vaporized in the process . Heat required for vaporization = m x 540x4.2 = 2268m J
Heat required to warm the water of 85 g to 100 °C = 85X4.2 X 80 = 28560 J
heat lost = heat gained
37732.5 = 28560 + 2268m
m = 4 g.
So 4 g of water will be vaporized and remaining 81 g of water and 130 g of iron that is total of 211 g will be in the cup . final temp of water will be 100 °C.
Answer:
Cost = 40 fills
Explanation:
First, we will calculate the total power consumed by all appliances:
Now, we will calculate the energy required:
Now, for the cost we use the following formula:
<u>Cost = 40 fills</u>
