-- Light travels straight, not around in a circle. But if it did, it would cover
a distance equal to the length of the equator in about <em>0.13 second</em>.
-- At the speed of sound (in air at standard temperature and pressure),
it would take about <em>32.6 hours </em>to cover the same distance.
Answer:
a) 19.4 m/s
b) 19 m/s
Explanation:
a) In the given question,
the potential energy at the initial point = Ui = 0
the potential energy at the final point = Uf = mgh
the kinetic energy at the initial point = Ki = 1/2 mv₀².
the kinetic energy at the final point = Kf = 0
work done by air= Ea= fh = 0.262 N
Now, using the law of conservation of energy
initial energy= final energy
Ki +Ui = Kf + Uf +Ea
1/2 mv₀² + 0 = 0 + mgh + fh
1/2 mv₀² = mgh + fh
h = v₀²/ 2g (1 +f/w)
calculate m
m= w/g = 5.29 /9.8
= 0.54 kg
h = 20 ²/ (2 x9.80) x (1 0.265/5.29)
h = 19.4 m.
b) 1/2 mv² + 2fh = 1/2 mv₀²
Vg = 19 m/s
Consider 20 deg.C. as room temperature.
From tables,
Silver has a resistivity of 1.6*10^-8 ohm-m at 20 deg.C, and it increases by 0.0038 ohm-m per deg.K increase.
Therefore if the temperature rise above 20 deg.C is T, then silver will have resistivity of
1.6*10^-8(1 + 0.0038T) ohm-m
At room temperature, the resistivity of tungsten (from tables) is 5.6*10^-8.
The resistivity of silver will be 4 times that of tungsten (at room temperature) when
1.6*10^-8(1 + 0.0038T) = 4*5.6*10^-8
1 + 0.0038T = 14
T = 13/.0038 = 3421 deg.K approx
Answer: 20 + 3421 = 3441 °C
Answer:
A
Explanation:
An antifreeze is a substance which when added to a liquid reduces the freezing point of the liquid. Hence the solution can only freeze at a lower temperature compared to the solvent. Examples of antifreeze includes salt and propylene glycol. Antifreeze are used in low temperature environments to prevent water from freezing quicky. Hence the answer is A.
Have a great day Aylabailey4930
Answer:
Yes, the relationships you observe in childhood affects the quality of your current relationships.
Explanation:
The saying,<em> "Children see, children do,"</em> is evidently true. A child's lifestyle and future relationships are greatly affected by the kind of relationships you allow him to see. Thus, it is very important that parents become role models for their kids.
For example, when your parents handle stress by shouting at each other, then most likely you'd also handle stress the same way in the future. So,<em> it is essential that the role models will show the child how to handle stress positively.</em> The experiences that children have at a young age affects their adult life.<u> It influences them and shapes them into who they will become.</u>
If people at home show positive relationships with each other and also supports a child regarding his education, then the child will most likely set positive relationships with his peers and achieve higher degree standards.
Thus, this explains the answer.
