Il A shooting star is actually the track of a meteor, typically a small chunk of debris from a comet that has entered the earth's atmosphere. As the drag force slows the meteor down, its kinetic energy is converted to thermal energy, leaving a glowing trail across the sky. A typical meteor has a surprisingly small mass, but what it lacks in size it makes up for in speed. Assume that a meteor has a mass of 1.5 g and is moving at an impressive 50 km/s, both typical values. What power is generated if the meteor slows down over a typical 2.1 s? Can you see how this tiny object can make a glowing trail that can be seen hundreds of kilometers away? 61. a. How much work does an elevator motor do to lift a 1000 kg elevator a height of 100 m at a constant speed? b. How much power must the motor supply to do this in 50 s at constant speed?

Respuesta :

Answer:

Il. P = 892,857.14 Watt. Yes, I can see it.

61.a. W = 981,000 J

61.b. P = 19,620 Watt

Explanation:

Il.

m = 1.5 g = 0.0015 Kg

v = 50 km/s = 50,000 m/s

t = 2.1 s

[tex]Ke = \frac{1}{2}mv^{2}=(0.5)(0.0015kg)(50,000m/s)^{2}=1,875,000 J[/tex]

[tex]P = \frac{Ke}{t}= \frac{1,875,000 J}{2.1s}=892,857.14 Watt[/tex]

Answer: Yes, I can see it.

61.a.

m = 1,000 kg

[tex]g=9.81m/s^{2}[/tex]

h = 100 m

[tex]W=mgh=1,000kg*9.81m/s^{2}*100m =981,000 J[/tex]

61.b.

t = 50 s

[tex]P=\frac{W}{t}= \frac{981,000J}{50s} = 19,620Watt[/tex]

Hope this helps!