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3 years ago

If you are going to see which food dye diffuses fastest in water. Which variables do you measure How will you do this?

1 answer:

6 0

You should be searching for your independent variable, and think about every variable to keep the same. The only thing that should be changing between separate experiments would be the type of food dye, you keep the amount of dye used, the place you're distributing to, the location, temp... the list goes on. Your dependent variable is the outcome: Which food dye diffuses first.

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Based on Archimedes' principle, we know that if an object displaces a given weight of water, then the object is being buoyed up

Virty [35]

True. If the amount displaced is more than the mass, it floats. If the amount is less than the mass, it will sink.

8 0

2 years ago

Read 2 more answers

If a marathon runner averages 9.51 mi/hr, how long does it take him to run a 26.220-mile marathon. Express your answers in hours

ASHA 777 [7]

Explanation:

Speed of the marathon runner, v = 9.51 mi/hr

Distance covered by the runner, d = 26.220 mile

Let t is the time taken by the marathon runner. We know that the speed of the runner is given by total distance divided by total time taken. Mathematically, it is given by :

$v=\dfrac{d}{t}$

$t=\dfrac{d}{v}$

$t=\dfrac{26.220\ mi}{9.51\ mi/hr}$

t = 2.75 hours

Since, 1 hour = 60 minutes

t = 165 minutes

Since, 1 minute = 60 seconds

t = 9900 seconds

Hence, this is the required solution.

7 0

3 years ago

There is a refrigerator running in a room, the heat flowing into the refrigerator from the outside is 40 J/s, and the refrigerat

Mamont248 [21]

Answer:

(A) 140 j/sec (b) 1.26 K

Explanation:

We have given the heat heat flowing into the refrigerator = 40 J/sec

Work done = 40 W

(a) So the heat discharged from the refrigerator $=heat\ flowing\ in\ refrigerator+work\ done=40+100=140j/sec$

(b) Total heat absorbed =140 j/sec $=140\times 3600=504000j/hour$

Let the temperature be $\Delta T$

Heat absorbed per hour =504000 $[tex]=400\times 10^3\times \Delta T$

So $\Delta T=\frac{504000}{400000}=1.26K$

8 0

3 years ago

A projectile is launched with an initial speed of 60.0 m/s at an angle of 30.0° above the horizontal. The projectile lands on a

vodka [1.7K]

Answer:

51.96 m/s^-1

Explanation:

a) see the attachment

b) As we know the velocity of the projectile has two component, horizontal velocity v_ox. and vertical velocity v_oy as shown in the figure. At the highest point of the trajectory, the projectile has only horizontal velocity and vertical velocity is zero. Therefore at the highest point of the trajectory, the velocity of the projectile will be

v_ox=v_o*cosФ

=60*cos (30)

= 51.96 m/s^-1

3 0

3 years ago

Read 2 more answers

A battery does work on electric charges to bring them to a position of higher electric potential energy so that they can flow th

Ipatiy [6.2K]

(Missing question is: which of the following statements are true?)

a) A battery does work on electric charges to bring them to a position of higher electric potential energy so that they can flow through a circuit to a lower potential energy --> TRUE
That's true: the battery does the work to move the charges to one end of its terminal thus creating a potential difference between the two terminals. Then, when it is connected to the circuit, charges start to flow to the terminal at lower potential (through the circuit)

b) the potential difference between the terminals of a battery, when no current flows to an external circuit, is referred to as the terminal voltage --> FALSE
This is false: when no current flows, it is called e.m.f. (electromotive force)

c) the internal resistance of a battery decreases with decreasing temperature
--> TRUE
In fact, the dependence of a resistance with the temperature is:
 $R=R_0[1+\alpha (T-T_0)]$
with $\alpha$ being generally positive, therefore the value of the resistance is proportional to T, and when T decreases, R decreases as well.

d) a battery is a device that produces electricity by transforming chemical energy into electrical energy --> TRUE
That's true: a battery uses chemical reactions to create a potential difference between the two terminals that can be exploited to make charges flowing through a circuit.

7 0

3 years ago