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3 years ago

14

Give at least two examples where people commonly use temperature to control reaction rates.

1 answer:

wariber [46]3 years ago

7 0

The examples may be;
making yogurt; If you heat beyond 130F you kill the cultures. The higher the temperature up until that point the faster it cultures until you close in on killer temperature.
Mixing 2 part epoxy; Keep it cool and the reaction time is delayed. On the other hand, heat it up and epoxy reacts quicker. In the winter time and close to 35 Degrees, the reaction time for cement to harden can take 400% more time to set.

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A mass on a spring vibrates in simple harmonic motion at an amplitude of 8.0 cm. If the mass of the object is 0.20 kg and the sp

Dmitry [639]

Answer:

Frequency, f = 3.73Hz

Explanation:

The frequency of a simple harmonic 6is given by:

f = w/2pi

But w= Sqrt( k/m)

Where k is the spring constant

And m is the mass

Given:

Mass=0.20kg

Spring constant, k=130N/m

w= Sqrt(130/0.20)

w= Sqrt(650)

w= 25.50 m

Frequency, f = w/2pi

f = 25.50/(2×3.142)

f = 3.73Hz

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4 years ago

Assuming 84.0% efficiency for the conversion of electrical power by the motor, what current must the 13.0-V batteries of a 716 k

tino4ka555 [31]

Answer:

$\mathbf{ current(I) =1766.67 \ A}$

Explanation:

Given that:

The air resistance and friction = 700 N

The gravity caused force = 716 × 9.8 = 7016.8

Total force = (7016.8 + 700) N

Total force = 7716.8 N

∴

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$current(I) \times 10.92= 19292$

$current(I) = \dfrac{19292}{10.92}$

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3 years ago

A plane starting from rest accelerates at 3m/s2 for 25s. Calculate the increase in velocity after:

horsena [70]

Initial velocity=u=0m/s
Acceleration=a=3m/s^2

Time not needed now

Case-1:-

Time=1s
Final velocity=v

$\\ \rm\hookrightarrow v=u+at$

$\\ \rm\hookrightarrow v=0+3(1)$

$\\ \rm\hookrightarrow v=3m/s$

Case-2:-

Time=3s

$\\ \rm\hookrightarrow v=0+3(3)$

$\\ \rm\hookrightarrow v=9m/s$

Case-3:-

Time=25s

$\\ \rm\hookrightarrow v=0+3(25)$

$\\ \rm\hookrightarrow v=75m/s$

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3 years ago

A 18.5-cm-diameter loop of wire is initially oriented perpendicular to a 1.9-T magnetic field. The loop is rotated so that its p

Alchen [17]

Answer:

0.3405V

Explanation:

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$\phi=B.(\pi r^2)cos 0\textdegree\\=1.9\pi\times 0.0925^2 \times cos 0\textdegree\\=5.107\times10^-^2 \ Tm^2$

we can now calculate the induced emf, $\frac{\phi}{\bigtriangleup t}$ :

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3 years ago

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Ad libitum [116K]

Answer:

74.52s

Explanation:

The solution is shown in the picture below

7 0

3 years ago