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3 years ago

Calculate the heat added to 3kg of water if the temperature increases from 30 C to 60 C.

Physics

1 answer:

sweet-ann [11.9K]3 years ago

5 0

Answer: B is right

Explanation: Heat Q = m Cv ΔT = 3.0 kg · 4186 J / (kg·K) · 30 K≈ 376 740 J

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what will the stopping distance be a a 3000-kg car if -3000N of force are applied when the car is traveling 10 m/s

Inga [223]

Answer:

50 m

Explanation:

Acceleration= force/mass

3000/3000=1m/s^-2

Applying equation of motion:

V^2=U^2+2as; V is final velocity, u is initial velocity, a is acceleration and s is the distance covered.

0=10^2 -2*1s;

Solve for s

5 0

3 years ago

In a large centrifuge used for training pilots and astronauts, a small chamber is fixed at the end of a rigid arm that rotates i

RSB [31]

a) The length of the arm of the centrifuge is 10.9 m

b) The angular acceleration is $2.7 rad/s^2$

Explanation:

In a uniform circular motion, the centripetal acceleration is given by

$a_c=\omega^2 r$

where:

$\omega$ is the angular speed of the circular motion

r is the radius of the circle

For the centrifuge in this problem, we have:

$\omega=1.7 rad/s$ is the angular speed

The centripetal acceleration is 3.2 times the acceleration due to gravity ( $g=9.8 m/s^2$ ), so:

$a_c=3.2 g = 3.2(9.8)=31.4 m/s^2$

Therefore, we can re-arrange the previous equation to find r, the radius of the circle (which corresponds to the length of the arm of the centrifuge):

$r=\frac{a_c}{\omega^2}=\frac{31.4}{1.7^2}=10.9 m$

In the second part of the exercise, the centrifuge speeds up from an initial angular speed of 0 to a final angular speed of 1.7 rad/s. The total acceleration experienced at the final moment is

$a=4.4 g$

So, 4.4 times the acceleration due to gravity.

The total acceleration is the resultant of the centripetal acceleration ( $a_c$ ) and the tangential acceleration ( $a_t$ ):

$a=\sqrt{a_c^2+a_t^2}$

We know that:

a = 4.4g

$a_c = 3.2 g$

So, we can find the tangential acceleration:

$a_t = \sqrt{a^2-a_c^2}=\sqrt{(4.4g)^2-(3.2g)^2}=29.6 m/s^2$

The angular acceleration is related to the tangential acceleration by

$\alpha = \frac{a_t}{r}$

where r = 10.9 m is the length of the centrifuge. Substituting,

$\alpha = \frac{29.6}{10.9}=2.7 rad/s^2$

Learn more about centripetal and angular acceleration here:

brainly.com/question/2562955

brainly.com/question/9575487

brainly.com/question/9329700

brainly.com/question/2506028

#LearnwithBrainly

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3 years ago

A circular window of 30 cm diameter in a submarine can withstand a maximum force of 5.20 × 105 N. The maximum depth in a lake to

Svetach [21]

Answer: Option (b) is the correct answer.

Explanation:

The given data is as follows.

F = $5.20 \times 10^{5}$ N

g = 9.8 m/s

radius = $\frac{diameter}{2}$

= $\frac{30 cm}{2}$ = 15 cm = 0.15 m (as 1 m = 100 cm)

Formula to calculate depth is as follows.

F = $\rho \times g \times h \times A$

or, h = $\frac{F}{\rho \times g \times A}$

h = $\frac{5.2 \times 10^{5}}{1000 \times 9.8 \times (3.1416 \times (0.15 m^{2})}$

= 751 m

Thus, we can conclude that the maximum depth in a lake to which the submarine can go without damaging the window is closest 750 m.

3 0

3 years ago

How many total oxygen atoms are in the compound Molybdenum (V) Dichromate?

alekssr [168]

Answer:

$1.2646\times10^{25}\ atoms$

Explanation:

-The chemical formula for Molybdenum (V) Dichromate is $Mo(Cr_2O_7)_3$

-There are 21 moles of oxygen per one mole of Molybdenum (V) Dichromate

-We apply Avogadro's constant to find the number of atoms of oxygen:

$Avogadro's \ Constant=6.022\times 10^{23} \ mol_1\\\\No\ of \ Atoms=Moles\times Avogadro's \ Constant\\\\=21\times 6.022\times 10^{23} \\\\=1.2646\times10^{25}\ atoms$

Hence, there are $1.2646\times10^{25} \ atoms$

3 0

3 years ago

Please help I’ll give brainliest

lesya [120]

Answer:

Objects that have like charges attract each other.

Objects that have opposite charges repel each other.

When fur is rubbed on the balloon electrons move from the balloon to the fur.

This is because the balloon's material is an insulator.

Electrons have negative charge.

Protons have a positive charge.

neutrons have no charge.

Explanation:

4 0

3 years ago