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3 years ago

How do changes in light wavelengths support the big bang theory?

2 answers:

5 0

Lights from other galaxies shifts toward the red end of the spectrum, which shows that the galaxies are moving away from the earth. (A)

likoan [24]3 years ago

5 0

Answer: A

Explanation:

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A 3.00 kg object is fastened to a light spring, with the intervening cord passing over a pulley. The pulley is frictionless, and

finlep [7]

Answer:

Part a)

k = 588.6 N/m

Part b)

v = 0.7 m/s

Explanation:

As we know that initially block is at rest

now if block is released from rest then it will go down by 10 cm and again comes to rest

so here we have

Part a)

Work done by gravity + work done by spring force = change in kinetic energy

$W_g + W_{spring} = 0 - 0$

$mg(0.10) + \frac{1}{2}k(0^2 - 0.10^2) = 0$

$3(9.81)(0.10) - \frac{1}{2}k(0.10)^2 = 0$

$k = 588.6 N/m$

Part b)

Now when spring is stretch by x = 5 cm then the speed of the block is given as

$mgx' + \frac{1}{2}k(0^2 - x'^2) = \frac{1}{2}mv^2 - 0$

here we have

$x' = 0.05 m$

$3(9.81)(0.05) - \frac{1}{2}(588.6)(0 - 0.05^2) = \frac{1}{2}(3) v^2$

$1.4715 - 0.736 = 1.5 v^2$

$v = 0.7 m/s$

3 0

3 years ago

How much electrical potential energy is stored in a capacitor that has 8.0 × 10-10 C of charge on each plate and a potential dif

arsen [322]

THere is a standard relationship that gives this result where the capacity of the capacitor is used:
$E=1/2* \frac{Q^2}{C}$ .
We know though that Q/c=V and thus we can use the relationship:
E=Q*V/2 where we have just substituted in. If we also take into account that Q=VC, we can also get that E=V^2*C/2.
We are given the charge and the potential, so the best expression to use is the middle one.
Substituting, we get that E=1/2*8*10^(-10)*20=8*10^(-9).

The answer is B

8 0

3 years ago

Why is energy transferable?

disa [49]

Kinetic Energy. Energy is transferred from one object to another when a reaction takes place. Energy comes in many forms and can be transferred from one object to another as heat, light, or motion, to name a few. ... This energy would be in the form of motion, with the person lifting the blue ball to a higher level.

3 0

3 years ago

Explain why ice melts in a cup at room temperature, in terms of energy transfer and the second law of thermodynamics.

zlopas [31]

Answer:

The second law of thermodynamics describes the direction in which heat is transferred between systems, heat is a form of energy in transition.

This law says that heat or energy always flows spontaneously from the body or system with a higher temperature to a lower temperature system (from something hot to something cold, and not the other way around).

This is why if we leave an ice at room temperature it will eventually melt, because the environment transferred energy to the ice and caused its temperature to increase and thus to turn into a liquid form.

The second law can also be interpreted in terms of entropy, and tells us that entropy, which is often interpreted as a measure of disorder, always increases.

4 0

3 years ago

Car enthusiasts often lower their cars closer to the ground as a matter of style. James wants to lower his car by replacing all

Alexandra [31]

Answer:

$\Delta h=0.0364\ m=3.64\ cm$