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3 years ago

15

Jamal combined baking soda and vinegar but he is having trouble determining if what he observed is a chemical reaction or a phys

ical change. a.change in color
b. absorption of heat
c. no change on properties
d. formation of new substances

2 answers:

maria [59]3 years ago

4 0

D is the answer............

KonstantinChe [14]3 years ago

4 0

D.<span>formation of new substances i hope this helps you

</span>

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A lightbulb is rated by the power that it dissipates when connected to a given voltage. For a lightbulb connected to 120 V house

zhenek [66]

1. increase, 2. decrease

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3 years ago

Determine in symbols an expression for the magnetic force exerted on the falling bar (and determine the direction of that force)

Katarina [22]

Answer:

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direction of the force is vertically upwards

Explanation:

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A pitcher is in 85° of abduction, holding a 1.4 N baseball at point C, 65 cm from the joint axis at point O • The center of grav

erastovalidia [21]

I attached a Diagram for this problem.

We star considering the system is in equlibrium, so

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$W+1.4-Fm cos(70)$

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Substituting,

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$Fm = \frac{7.4}{cos(70)}$

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<em>For the second part we know that the reaction force Fj on deltoid Muscle is equal to Fm, We can assume also that</em> $\beta = \theta$

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3 years ago

A car and a train move together along straight, parallel paths with the same constant cruising speed v(initial). At t=0 the car

kogti [31]

Answer:

$t_1 = \frac{v_i}{a_i}$

$t_2 = \frac{v_i}{a_i}$

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$v_i = 0 + a_it_2\\t_2 = \frac{v_i}{a_i}$

As $s(t) = vt + \frac{at^2}{2}$ . After $t = t_1 + t_2$ , the car would have traveled a distance of

$s(t) = s(t_1) + s(t_2)\\s(t_1) = (v_it_1 - \frac{a_it_1^2}{2})\\ s(t_2) = \frac{a_it_2^2}{2}$

Hence $s(t) = (v_it_1 - \frac{a_it_1^2}{2}) + \frac{a_it_2^2}{2}$

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Therefore, Δd would be $2v_it_1 - v_it_1 = v_it_1 = v_i^2/a_i$

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3 years ago

If we warm a volume of air, it expands. Does it then follow that if we expand a volume of air, it warms? Explain.

Ivahew [28]

Answer:

nope don't think so

Explanation:

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3 years ago

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