3 years ago

A train travels 80 kilometers in 2 hours, and then 79 kilometers in 4 hours. What is its average speed?

Physics

1 answer:

Ludmilka [50]3 years ago

4 0

79 2/3 kilometers per hour

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A car is traveling at a speed of 10m/s. A 0.5kg clump of mudis

CaHeK987 [17]

Answer:B

Explanation:

Given

speed of car $v=10 m/s$

mass of clump $m=0.5 kg$

Radius of car tire $r=0.2 m$

Since the tire is rotating about axle so a centripetal force is acting constantly on each particle towards the center of tire.

Centripetal force is given by

$F_c=\frac{mv^2}{r}$

where $m=mass\ of\ element$

$v=speed$

$r=distance\ from\ center$

$F_c=\frac{0.5\times 10^2}{0.2}$

$F_c=250\ N$ (inward)

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3 years ago

Unlike velocity, speed is scalar, which means it is described by ______<br> only.

natali 33 [55]

Hi there,

Unlike velocity,speed is scalar,which means it is described by MAGNITUDE only.

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3 years ago

Read 2 more answers

Like the filters falling through the air, a car on the freeway represents an object with a high Reynolds number traveling throug

Goshia [24]

Answer:

ΔF=125.22 %

Explanation:

We know that drag force on the car given as

$F_D=\dfrac{1}{2}\rho C_DA v^2$

$C_D$ =Drag coefficient

A=Projected area

v=Velocity

ρ=Density

All other quantity are constant so we can say that drag force and velocity can be given as

$\dfrac{F_D_1}{F_D_2}=\dfrac{v_1^2}{v_2^2}$

Now by putting the values

$\dfrac{F_D_1}{F_D_2}=\dfrac{v_1^2}{v_2^2}$

$\dfrac{F_D_1}{F_D_2}=\dfrac{50^2}{75^2}$

$\dfrac{F_D_1}{F_D_2}=0.444$

Percentage Change in the drag force

$\Delta F=\dfrac{F_D_2-F_D_1}{F_D_1}\times 100$

$\Delta F=\dfrac{F_D_2-0.444F_D_2}{0.444F_D_2}\times 100$

$\Delta F=\dfrac{1-0.444}{0.444}\times 100$

ΔF=125.22 %

Therefore force will increase by 125.22 %.

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3 years ago

Convert 123,453 to a scientific notation

Natalija [7]

Answer:

1.23453*10^5 is scientific way

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3 years ago

Two charges repel each other with a force. If the magnitude of both charges double, but the distance between them remains consta

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Answer:

Explanation:

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3 years ago