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3 years ago

Explain how the technology of doing math and adding numbers has changed over time this is science

1 answer:

7 0

It has changed because earlier in the days people couldn't even figure out if the world was flat or round but now we can add decimals and multiply fractions.

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When studying atoms, scientists can ignore the ______ force between charged particles that make up the atoms because it is many

MArishka [77]

Answer:

Gravitational

Explanation:

When studying atoms, scientists can ignore the gravitational force between charged particles that make up the atoms because it is many millions of times smaller than other forces in the atom.

6 0

3 years ago

Read 2 more answers

Newton's law of cooling is , where is the temperature of an object, is in hours, is a constant ambient temperature, and is a pos

kirill [66]

Complete Question

The complete question is shown on the first uploaded image

Answer:

The time taken is $t = 6.89 \ hrs$

Explanation:

From the question we are told that

The value of $k = 0.15hr^{-1}$

The the interior temperature is $u(t = 0) = 70 ^oF$

The external temperature is $T = 11 ^oF$

The required interior temperature is $u_{t} = 32 ^oF$

The newton cooling law is

$\frac{du}{dt} = -k (u -T)$

=> $\frac{du}{u-T} = - kdt$

Now integrate both sides we have

$\int\limits \frac{du}{u-T} =\int\limits - kdt$

$ln (u - T) = -kt + c$

Since c is a constant lnC = c will also give a constant so

$ln (u - T) = -kt + ln C$

=> $\frac{(u -T)}{C} = e^{-kt}$

=> $u = T + Ce^{-kt}$

substituting value

$70 = 11 +Ce^{-0* 0.15}$

$C = 59$

Hence

$u_t = 11 + 59 e^{-0.15 *t}$

$32= 11 + 59 e^{-0.15 *t}$

=> $t = -\frac{ln(\frac{21}{59} )}{0.15}$

$t = 6.89 \ hrs$

3 0

3 years ago

A 12.6-kg monkey is hanging by one arm from a branch and swinging on a vertical circle. As an approximation, assume a radial dis

Zinaida [17]

Answer:

a)27.3N

b)150.78N

Explanation:

Having in mind the conservation of energy, as the monkey goes up (gaining potential gravitational energy) the kinetic energy must be reduced, so reducing the velocity of the monkey. So the maximum velocity will be at this lower point with a velocity of 1.36m/s

From this velocity and the radius we can calculate the angular velocity for the monkey center of mass:

$w=\frac{1.36m/s}{0.853m} =1.594 /s$

with this we can calculate the centripetal force magnitude:

$F=m*w^{2} *r=12.6kg*(1.594/s)^{2} *0.853m=27.3N$

On the mokey center of mass we have two opposite forces acting, the tension of the arm and the weight, in order for the monkey to continue swinging the resolt of this two forces must be equal to the centripetal force:

$T-P=F=>T=F+P$

$T=27.3N+12.6kg*9.8m/s^{2}=150.78N$

8 0

3 years ago

On a foggy day, you are driving at 70 mph and Granny is driving at 50 mph. As you try to pass her, you both see an overturned tr

Vitek1552 [10]

Answer:

Explanation:

7 0

3 years ago

The drawings show three examples of the force with which someone pushes against a vertical wall. In each case the magnitude of t

Monica [59]

Complete Question

The complete question is shown on the

Answer:

The ascending order would be 2nd < 1st < 3rd

Explanation:

Generally the the Normal force is mathematically represented as

$Normal \ Force = Fsin \theta$

=> $Normal \ Force \ \alpha \ sin \theta$

For the first drawing the value $\theta$ is between that of the the second and the third drawing so the Normal force would also be between the normal forces of the second and the third drawing

For the second drawing whose value of $\theta$ is less than that of the first and the third the normal force would also be less than that of the first and third

For the the third drawing whose value is (90°) which is higher than the first and the second the normal force would also be higher than the first and the second

4 0

3 years ago

Read 2 more answers