All categories

2 years ago

You just competed in a track meet and you run the 1500m race in 403 s. what was your average speed in miles per hour

Chemistry

1 answer:

miss Akunina [59]2 years ago

4 0

Answer:

8.46mph

Explanation:

Given parameters:

Distance run = 1500m

Time taken to cover distance = 403s

Unknown:

Average speed in mph = ?

Solution:

The average speed of a travel is the rate of change of the total distance with time.

Speed is a scalar quantity that specifies magnitude of the travel but no direction.

Average speed = $\frac{Total distance covered }{Time taken}$

we need to covered distance to miles from m and time in seconds to hours.

1609m = 1 mile

1500m = $\frac{1500}{1609}$ = 0.93miles

3600s = 1hr

403s = $\frac{403}{3600}$ = 0.11hr

Average speed = $\frac{0.93}{0.11}$ = 8.46miles per hour

You might be interested in

Explain the states of solid, liquid and gas in terms of molecular movement and molecular packing?*

lora16 [44]

Solid- molecules vibrate in place and tightly packed
liquid-molecules fur shape of container and can slide past each other
gas-molecules also fit shape of container and have the most room

7 0

2 years ago

Define significant figure. Discuss the importance of using the proper number of significant figures in measurements and calculat

anastassius [24]

Explanation:

Significant figure is the measure of how accurately something can be measured. It carries meaning contributing to its measurement resolution. It is important to use proper number of significant figures to get a precise measurement. For example, if we use a meter stick then measurements like 0.874 meters, or 0.900 meters, are good because they indicate that we can measure to the nearest millimeter. Whereas a measurement like 0.8 does not tell that a meter stick can measure to the nearest millimeter.

7 0

2 years ago

Why do you use the same amount of water for each shape of ice?

Fiesta28 [93]

Answer:

Ice is a solid form of liquid. Water simply expands when it freezes.

The same amount of water for each shape of ice because the melting rate of ice depends on the surface area of each shape. So the same amount of water or volume with a large surface area will remain frozen for longer time.

4 0

2 years ago

Your teacher gives you a black powder. When you dissolve the powder in water, you see red particles that float to the top, black

laila [671]

The answer is B. A mixture can be separated as shown in the example.<span />

3 0

2 years ago

Read 2 more answers

When 7.085 grams of a hydrocarbon, CxHy, were burned in a combustion analysis apparatus, 21.71 grams of CO2 and 10.37 grams of H

Taya2010 [7]

Answer:

- Empirical:

$C_3H_7$

- Molecular:

$C_6H_{14}$

Explanation:

Hello,

In this case, based on the information regarding the combustion, the moles of carbon turn out:

$n_C=21.71gCO_2*\frac{1molCO_2}{44gCO_2}*\frac{1molC}{1molCO_2}=0.493molC$

Moreover, the moles of hydrogen:

$n_H=10.37gH_2O*\frac{1molH_2O}{18gH_2O}*\frac{2molH}{1molH_2O}=1.152molH$

Thus, the subscripts of carbon and hydrogen in the hydrocarbon turn out:

$C=\frac{0.4934}{0.4934}=1\\H=\frac{1.15222}{0.4934}=2.335\\CH_{2.335}$

Now, looking for a suitable whole number we obtain the following empirical formula as 2.335 times 3 is 7 for hydrogen:

$C_3H_7$

In such a way, that compound has a molar mass of 43 g/mol, thus, the whole compound's molar mass is 86.18 g/mol for which the molecular formula is twice the empirical one, therefore:

$C_6H_{14}$

Which is hexane.

Best regards.

6 0

2 years ago