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2 years ago

Consider a 0.63-kg sample of metal at room temperature of 20

1 answer:

3 0

It is to be noted that to answer this question, we only use the given mass and the given amount of heat needed to liquefy the object. The equation that we can use is,
Hf = mhf
where Hf is the amount of heat, m is the mass, and hf is the heat of fusion.
59400 J = (0.63 kg)hf
The value of hf from the equation is <em>94,285.71 J/kg</em>.

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If the voltage amplitude across an 8.50-nF capacitor is equal to 12.0 V when the current amplitude through it is 3.33 mA, the fr

Dmitriy789 [7]

Answer:

Frequency will be equal to 5.20 kHz

So option (c) will be correct answer

Explanation:

We have given value of capacitance $C=8.5nF=8.5\times 10^{-9}f$

Potential difference across capacitor V = 12 volt

Current through capacitor $i=3.33mA=3.33\times 10^{-3}A$

Capacitive reactance will be equal to $X_c=\frac{V}{i}=\frac{12}{3.33\times 10^{-3}A}=3603.60ohm$

Capacitive reactance is equal to $X_c=\frac{1}{\omega C}$

$3603.60=\frac{1}{\omega\times 8.5\times 10^{-9}}$

$\omega =32647.091rad/sec$

$2\pi f=32647.091$

$f=5198.98Hz$

f = 5.20 kHz

So frequency will be equal to 5.20 kHz

So option (c) will be correct answer

3 0

2 years ago

A box slides down a frictionless plane inclined at an angle θ ¸ above the horizontal. The gravitational force on the box is dire

DedPeter [7]

<h2>Answer: at an angle $\theta$ below the inclined plane. </h2>

If we draw the <u>Free Body Diagram</u> for this situation (figure attached), taking into account only the gravity force in this case, we will see the weight $W$ of the block, which is directly proportional to the gravity acceleration $g$ :

$W=m.g$

This force is directed vertically at an angle $\theta$ below the inclined plane, this means it has an X-component and a Y-component:

$W=W_{X}+W_{Y}$

$W_{X}=m.g.cos(\theta)$

$W_{Y}=m.g.sin(\theta)$

Therefore the correct option is c

6 0

2 years ago

Read 2 more answers

A dolphin swims due east for 1.90 km, then swims 7.20 km in the direction south of west. What are the magnitude and direction of

kykrilka [37]

Answer:

magnitude = 7.446 km, direction = 75.22° north of east

Explanation:

From the questions,

To get the the magnitude of the resultant vector we use Pythagoras theorem

a² = b²+c²

From the diagram,

y² = 1.9²+7.2²

y² = 55.45

y = √(55.45)

y = 7.446 km.

The direction of the dolphin is given as,

θ = tan⁻¹(7.2/1.9)

θ = tan⁻¹(3.7895)

θ = 75.22° north of east

Hence the magnitude of the resultant vector = 7.446 km, and it direction is 75.22° north of east

3 0

2 years ago

Buffalo, New York, experienced a snowstorm November 13–21, 2014. Residents refer to the event as “Snowvember.” What was the like

scZoUnD [109]

I know you're probably done with this by now, but the answer is *Lake-Effect Snow*

5 0

2 years ago

Read 2 more answers

Assume that segment r exerts a force of magnitude t on segment l. what is the magnitude flr of the force exerted on segment r by

mrs_skeptik [129]

If we are talking on the force being exerted by a segment of a rope of lenght R on the right on a point M which is being also pulled from the Left by a segment of rope R as shown in the figure attached. Then we invoke Newton's Third Law:
"Any force exerted by an object (in this case a segment of the rope) also suffers a equal and opposite force".
If we pick $T_R=T$ whis is the tension exerted by the right segment then the left segment will also exert an equal and opposite force so we have that $T_L=-T$

8 0

2 years ago