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3 years ago

A boat takes 4.0 h to travel 36 km down a river, then 5.0 h to return.how fast is the river flowing

1 answer:

5 0

Let us refer to boat speed as X and water speed as Y On the way down the stream, the water speed is added to the speed of the boat: speed of the boat (X) + water speed (Y) is 9km/h When the boat is moving upstream, water speed is taken away from the speed of the boat: Speed of the boat (X) - water speed (Y) is 7.2 km/h Therefore: X + Y = 9 : X - Y = 7.2 2X = 16.2 X = 8.1 X + Y = 9 8.1 + Y = 9 Y = 0.9 The river is flowing at 0.9 km/h

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An accelerating voltage

ki77a [65]

Accelerating voltage is the difference in potential between the filament and the anode,and it can be varied between 5 KeV and 30 KeV on the S-500 and between 2 KeV and 30 KeV on the S-450. As the voltage is increased, the electrons travel with higher velocity and are more energetic.

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3 years ago

Assume the following vehicles are all moving at the Sam speed .it would be harder to change the velocity of which vehicle . What

AVprozaik [17]

Answer:what the choices

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2 years ago

A "moving sidewalk" in an airport terminal moves at 1.0 m/s and is 35.0 m long. If a woman steps on at one end and walks at 1.5

pishuonlain [190]

Answer:

a.14 s

b.70 s

Explanation:

a.Let the sidewalk moving in positive x- direction.

Speed of sidewalk relative to ground= $v_s=1m/s$

Speed of women relative to sidewalk=v=1.5m/s

The speed of women relative to the ground

$v_w=v_s+v=1+1.5=2.5m/s$

Distance=35 m

Time= $\frac{distance}{speed}$

Using the formula

Time taken by women to reach the opposite end if she walks in the same direction the sidewalk is moving= $\frac{35}{v_w}=\frac{35}{2.5}=14s$

b.If she gets on at the end opposite the end in part (a)

Then, we take displacement negative.

Speed of sidewalk relative to ground= $v_s=1m/s$

Speed of women relative to sidewalk=v=-1.5 m/s

The speed of women relative to the ground= $v_w=v_s+v=1-1.5=-0.5m/s$

Time= $\frac{-35}{-0.5}=70 s$

Hence, the women takes 70 s to reach the opposite end if she walks in the opposite direction the sidewalk is moving.

3 0

3 years ago

Which of the following air conditions would be least likely to have precipitation?

Lynna [10]

The best and most correct answer among the choices provided by the question is the first choice "warm, dry air"

In meteorology, precipitation is any product of the condensation of atmospheric water vapor that falls under gravity. The main forms of precipitation include drizzle, rain, sleet, snow, graupel and hail.

I hope my answer has come to your help. God bless and have a nice day ahead!

7 0

3 years ago

Read 2 more answers

Help How much current will flow when a 120 V power supply is connected to a 30 resistor ?

AVprozaik [17]

Current= voltage divided by resistance
120/30=4

7 0

2 years ago