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2 years ago

Suppose a woman raises a 65 N object in 2m in 4 seconds.

Physics

1 answer:

Novosadov [1.4K]2 years ago

8 0

Answer:

$\huge\boxed{\sf P.E = 130\ Joules}$

$\huge\boxed{\sf P = 32.5\ Watts}$

Explanation:

Given Data:

Weight = W = 65 N

Height = h = 2 m

Time = t = 4 secs

Required:

Power = P = ?

Work Done in the form of Potential Energy = P.E. = ?

Formula:

P.E. = Wh

P = P.E. / t

Solution:

P.E. = (65)(2)

P.E = 130 Joules

P = P.E. / t

P = 130 / 4

P = 32.5 Watts

$\rule[225]{225}{2}$

Hope this helped!

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2 years ago

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Whenever we are solving a physics problem, it's really useful to start by drawing a diagram of the problem (See picture attached). It will help us visualize the problem better.

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$V_{plane y}=V_{plane/wind y}+V_{wind y}$

$V_{plane/wind y}=V_{plane y}-V_{wind y}$

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So the velocity of the plane with respect to the wind can be rewritten as:

$V_{plane/wind x}= (-39.71i + 205.67 j) km/hr$

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$speed=\sqrt{(-39.71)^{2}+(205.67)^{2} }$

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Therefore, the speed of the airplane relative to the air is 209.47km/hr

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