Which of the following is a theory stating that one plate is forced beneath another plate?

The average power dissipated in a 47 ω resistor is 2.0 w. what is the peak value i 0 of the ac current in the resistor?

pishuonlain [190]

The average dissipated power in a resistor in a ac circuit is:
$P=I_{rms}^2 R$
where R is the resistance, and $I_{rms}$ is the root mean square current, defined as
$I_{rms} = \frac{I_0}{\sqrt{2}}$
where $I_0$ is the peak value of the current. Substituting the second formula into the first one, we find
$P=( \frac{I_0}{\sqrt{2} } )^2 R = \frac{1}{2} I_0^2 R$
and if we re-arrange this formula and use the data of the problem, we can find the value of the peak current I0:
$I_0 = \sqrt{ \frac{2 P}{R} }= \sqrt{ \frac{2 \cdot 2.0 W}{47 \Omega} }=0.29 A$

4 0

2 years ago

A skier is pulled by a towrope up a frictionless ski slope that makes an angle of 12 degrees with the horizontal. The rope moves

MArishka [77]

Answer:

Explanation:

Given,

Work done by the rope 900 m/s.
Angle of inclination of the slope = $\theta\ =\ 12^o$
Initial speed of the skier = v = 1.0 m/s
Length of the inclined surface = d = 8.0 m

part (a)

The rope is doing the work against the gravity on the skier to uplift up to the inclined surface. Therefore the work done by the rope is equal to the work done on the skier due to the gravity

$\therefore W_r\ =\ W_g\ =\ 900\ J$

In both cases the height attained by the skier is equal. and the work done by gravity does not depend upon the speed of the skier.

part (b)

Initial speed of the skier = v = 1.0 m/s.

Rate of the work done by the rope is power of the rope.

$Power\ =\ \dfrac{\Delta W}{\Delta t}\\\Rightarrow P\ =\ \dfrac{\Delta W}{\dfrac{d}{v}}\\\Rightarrow P\ =\ \dfrac{\Delta W\times v}{d}\\\Rightarrow P\ =\ \dfrac{900\times 1.0}{8.0}\\\Rightarrow P\ =\ 112.5\ Watt$

Part (c)

Initial speed of the skier = v = 2.0 m/s.

Rate of the work done by the rope is power of the rope.

$Power\ =\ \dfrac{\Delta W}{\Delta t}\\\Rightarrow P\ =\ \dfrac{\Delta W}{\dfrac{d}{v}}\\\Rightarrow P\ =\ \dfrac{\Delta W\times v}{d}\\\Rightarrow P\ =\ \dfrac{900\times 2.0}{8.0}\\\Rightarrow P\ =\ 225\ Watt$

4 0

2 years ago

Alexandra is attempting to drag her 32.6 kg golden retriever across the wooden floor by applying a horizontal force. What force

vichka [17]

Answer:

230.26 N

Explanation:

Since the speed is constant, acceleration is zero hence the net force will be given by the product of mass, coefficient of friction and acceleration due to gravity

F=0.72*32.6*9.81=230.26 N

7 0

3 years ago

A physicist hangs a 150-g object on a spring whose spring constant is a value of 13.22 Newtons/meter and has a spring force of 2

Nataly_w [17]

Answer:

so the answer is this because the answer is that

Explanation:

and the reason why the answer is this and that is because the answer is that

4 0

2 years ago

Calculate the frequency if the number of revolutions is 300 and the paired poles are 50.

Andrei [34K]

Answer: A

Explanation: We know that f=p*n

f=50*300=15000 Hz = 15kHz.

Have a great day! <3

3 0

1 year ago