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2 years ago

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A child is in danger of drowning in the Merimac river. The Merimac river has a current of 3.1 km/hr to the east. The child is 0.

6 km from the shore and 2.5 km upstream from the dock. A rescue boat with speed 24.8 km/hr (with respect to the water) sets off from the dock at the optimum angle to reach the child as fast as possible. How far from the dock does the boat reach the child?

1 answer:

kolezko [41]2 years ago

4 0

In a problem where a child is danger form drowning from a river who has a current of 3.1km/hr to east and the child is 0.6km fro the shore and the upstream is 2,5km from the dock. So base on the question the boat with a speed of 24.8 km/hr is 1.9 km because the child is 0.6 km off the dock so 2.5 minus 0.6

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A mixed cost contains a variable element and a fixed element.

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ANSWER: 1.6N (forth option)

EXPLANATION:
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3 years ago

An electron and a proton each have a thermal kinetic energy of 3kBT/2. Calculate the de Broglie wavelength of each particle at a

S_A_V [24]

Answer:

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Solution:

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$\lambda_{e} = \frac{h}{p_{e}}$

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where

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$v_{e}$ = velocity of an electron

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Now,

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Now, to calculate the de-Broglie wavelength of proton, $\lambda_{e}$ :

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$}v_{p} = \sqrt{\frac{3\times 1.38\times 10^{- 23}\times 1800}{1.6726\times 10_{- 27}}}$

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Using eqn (4) in (3):

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<h2>please mark me as brainliest. ......</h2>

<h2>my friend. ....please help me .....</h2>

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