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.
In order to reduce the amount of energy lost due to heat flow, electricity is delivered to our homes using <u>d. low current</u>.
<u>Explanation</u>:
The presence of flow of electrons is said to be electricity. The electricity flows in one direction. The electricity enables function of the electrical devices and machines.
Heat is generated when the electricity flows from one place to another. So the energy is lost in the form of heat.
So to avoid the loss of energy, the electricity is delivered to home using low current. The strength of an electric current can be measured and represented in the unit of ampere.
Answer:
719
Explanation:
Conversion
1 picometer (pm) is equivalent to
meter
1 micrometer is equivalent to
meter
To find the number of layers, we divide the overal leaf thickness by the thickness of one atom hence dividing tex]0.125 × 10^{-6}[/tex] meter by
meter we get that the number of sheets will be as follows

Therefore, they are approximately 719 sheets
Answer:
Yes, the velocity of the object can reverse direction when its acceleration is constant. For example consider that the velocity of any object at any time t is given as: ... At At t = 0 sec, the magnitude of velocity is 2m/s and is moving in the forward direction i.e.v (t) = -2.
the answer is true acceleration is the change in distance over time.
hope this helps