Answer:
The temperature after half an hour is 
Solution:
As per the question;
Metabolic rate of the person is 3.0105 J/h
Temperature, T = 
Mass of the water, 
Time duration, t = 0.5 h = 30 min = 180 s
Now,
Heat, 
Thus heat transfer in half an hour:
Now, the temperature of water after half an hour, T' is given by:
where
s = 4186 J
Answer:
Mirage is an optical illusion due to the refraction of light as it travels through different layers of air at different temperature.
Explanation:
On a clear hot afternoon, the sun heats up the ground, and the ground heats up the air immediately above it. The result is that the air directly above the ground is hotter than the air above it, leaving the air layers with different refractive indies. Since refractive index decreases with increase in temperature, the air immediately above the ground bends the light that travels through it from the sky, directly into our eyes. The image seen is perceived to be reflected from the ground, but in an actual sense is a direct image of the sky, giving one the impression of seeing a pool of water on the ground.
The universal force that is effective over the longest distance between very massive objects like planets is Gravity
Answer: D
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X: positive
Y: negative
Explanation:
It's either A or D and I chose A and got it wrong.
