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3 years ago

You biked to the store in 10 minutes. The store was 3 km away. What was your average speed?

Physics

1 answer:

sineoko [7]3 years ago

4 0

Answer:

speed in km/min:

0.3km/min

speed in km/h:

18km/h

speed in m/s:

5m/s

Explanation:

the average speed is defined as:

$s=\frac{d}{t}$

where $s$ is the speed, $d$ is the distance traveled, and $t$ is the time

according to the statement:

$d=3km = 3,000m$

and

$t=10min=\frac{1}{6}h=600s$ (10 minutes are equal to a sixth of an hour which is 600 seconds)

Because the units in which the speed is required are not indicated, here are some options for the answer:

Depending on the units in which you need the speed, are the quantities you should use.

Speed in km / h (kilometers per hour):

$s=\frac{3km}{\frac{1}{6}h }\\ \\s=18km/h$

speed in m / s (meters per second):

$s=\frac{3,000m}{600s}\\ s=5m/s$

or the speed in km/min (kilometers per minute)

$s=\frac{3km}{10min}\\ s=0.3km/min$

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2 years ago

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Citrus2011 [14]

Answer:

(a) 0.345 T

(b) 0.389 T

Solution:

As per the question:

Hall emf, $V_{Hall} = 20\ mV = 0.02\ V$

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Hall emf, $V'_{Hall} = 69\ mV = 0.069\ V$

Now,

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Now, the expression for the electric field is given by:

$E_{Hall} = Bv_{d}sin\theta$ (1)

And

$E_{Hall} = V_{Hall}d$

Thus eqn (1) becomes

$V_{Hall}d = dBv_{d}sin\theta$

where

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$B = \frac{V_{Hall}}{v_{d}sin\theta}$ (2)

(a) When $\theta = 90^{\circ}$

$B = \frac{0.069}{0.2\times sin90} = 0.345\ T$

(b) When $\theta = 60^{\circ}$

$B = \frac{0.069}{0.2\times sin60} = 0.398\ T$

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2 years ago

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A 50.0 kg person is walking horizontally with constant acceleration of 0.25 m/s² inside an elevator. The elevator is also accele

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Answer:

The acceleration is in 2 D as in between east and south.

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2 years ago

A force acting over a large area will exert less pressure per square inch than the same force acting over a smaller area.

babunello [35]

Answer:

True

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2 years ago