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zhannawk [14.2K]

3 years ago

6

A car travels 30 km north in 25 min. and 40 km east in 35 min. What is the total time in hours? Be careful to carry over the pro

per number of significant figures when you convert to hours.

2 answers:

lapo4ka [179]3 years ago

4 0

Answer:

t = 1.0 hours

Explanation:

as we know that all the data is given here in 2 significant figures

so here we need to find the total time of the motion

that time must be in two significant figures

here we know that

$t_1 = 25 min$

$t_2 = 35 min$

so here total time is given as

$t = t_1 + t_2$

$t = 25 + 35$

$t = 60 min$

$t = 1.0 hour$

inna [77]3 years ago

3 0

25+35=60mins so 1.0 hours

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Step one : read the directions

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Why does it take more force to push a car than it takes to push a bicycle? Please fully explain

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The suspension system of a 2100 kg automobile "sags" 8.5 cm when the chassis is placed on it. Also, the oscillation amplitude de

Gennadij [26K]

Answer:

Part a)

$k = 6.06 \times 10^4 N/m$

Part b)

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Explanation:

Part a)

as the mass of the suspension system is given as

$m = 2100 kg$

also we have

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so now for force balance we have

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$(525)(9.81) = k(0.085)$

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Part b)

Now we know that amplitude decreases by 63% in each cycle

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so it is given as

$A = 0.37 A_o$

also we know

$A = A_o e^{-bt/2m}$

$0.37 A_o = A_o e^{-bt/2m}$

$\frac{bt}{2m} = 1$

$b = \frac{2m}{t}$

here t = time period of one oscillation

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$t = 2\pi\sqrt{\frac{m}{k}}$

$t = 2\pi\sqrt{\frac{525}{6.06 \times 10^4}}$

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Answer:

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So:

$M = \frac{16 m}{12 cm}$

Care must be taken with the units, in this case they are in meters and centimeters, they should be converted into the same unit before calculating:

$M = \frac{16 m}{0.12 m} = 133$

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grandymaker [24]

The acceleration of gravity (on Earth) is 9.8 m/s² downward.

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2 years ago