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4 years ago

How much power does a toaster have if it does 21,000 joules of work in 30 seconds?

1 answer:

5 0

Power = (work done) / (time to do the work)

   = (21,000 Joules) / (30 seconds)

   = (21,000 / 30) joule/sec

   =    700 watts

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The distance between stars is typically measured in

Gelneren [198K]

The correct answer is Light years

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4 years ago

Read 2 more answers

If a sinusoidal electromagnetic wave with intensity 18 W/m2 has an electric field of amplitude E, then a 36 W/m2 wave of the sam

Neporo4naja [7]

Answer:

The correct option is D

Explanation:

From the question we are told that

The intensity of the first electromagnetic wave is $I = 18 \ W/m^2$

The amplitude of the electric field is $E_{max}_1 =A$

The intensity of the second electromagnetic wave is $I = 36 \ W/m^2$

Generally the an electromagnetic wave intensity is mathematically represented as

$I = \frac{1}{2} * \epsilon_o * c * E_{max}^2$

Looking at this equation we see that

$I \ \ \alpha \ \ E^2_{max}$

=> $\frac{I_1}{I_2} = [ \frac{ E_{max}_1}{ E_{max}_2} ] ^2$

=> $E_{max}_2 = \sqrt{\frac{x}{y} } * E_{max}_1$

=> $E_{max}_2 = \sqrt{\frac{36}{18} } * E$

=> $E_{max}_2 = \sqrt{2 } E$

5 0

3 years ago

A uniform meter stick is pivoted at the 50.00 cm mark on the meter stick. A 400.0 gram object is hung at the 20.0 cm mark on the

babunello [35]

Answer:C

Explanation:

Given

mass $m_1=400\ gm$ is at $x=20\ cm$ mark

mass $m_2=320\ gm$ is at $x=75\ cm$ mark

Scale is Pivoted at $x=50\ cm mark$

For scale to be in equilibrium net torque must be equal to zero

Taking ACW as positive thus

$T_{net}=0.4\times g\times (0.5-0.2)-0.32\times g\times(0.75-0.50)$

$T_{net}=0.12g-0.08g=0.04g$

Therefore a net torque of 0.04 g is required in CW sense which a mass $400\ gm$ can provide at a distance of $x_o$ from pivot

$0.04g=0.4\times g\times x_o$

$x_o=0.1\ m$

therefore in meter stick it is at a distance of $x=60\ cm$

6 0

3 years ago

A small plastic sphere of mass 2.0 g is charged to −5.0 nC and held 2.5 cm above a small glass bead of mass 0.015 g resting on a

LenKa [72]

Answer:uhhh

Explanation:

Uhhhh

5 0

4 years ago

The tub of a washer goes into its spin-dry cy-cle, starting from rest and reaching an angularspeed of 3.1 rev/s in 10.7 s.At thi

neonofarm [45]

Answer:

35 revolutions

Explanation:

t = Time taken

$\omega_f$ = Final angular velocity

$\omega_i$ = Initial angular velocity

$\alpha$ = Angular acceleration

$\theta$ = Number of rotation

Equation of rotational motion

$\omega_f=\omega_i+\alpha t\\\Rightarrow \alpha=\frac{\omega_f-\omega_i}{t}\\\Rightarrow \alpha=\frac{3-0}{10.7}\\\Rightarrow \alpha=0.28037\ rev/s^2$

$\omega_f^2-\omega_i^2=2\alpha \theta\\\Rightarrow \theta=\frac{\omega_f^2-\omega_i^2}{2\alpha}\\\Rightarrow \theta=\frac{3.1^2-0^2}{2\times 0.28037}\\\Rightarrow \theta=17.13806\ rev$

Number of revolutions in the 10.7 seconds is 17.13806

$\omega_f=\omega_i+\alpha t\\\Rightarrow \alpha=\frac{\omega_f-\omega_i}{t}\\\Rightarrow \alpha=\frac{0-3.1}{11.2}\\\Rightarrow a=-0.27678\ rev/s^2$

$\omega_f^2-\omega_i^2=2\alpha \theta\\\Rightarrow \theta=\frac{\omega_f^2-\omega_i^2}{2\alpha}\\\Rightarrow \theta=\frac{0^2-3.1^2}{2\times -0.27678}\\\Rightarrow \theta=17.36035\ rev$

Number of revolutions in the 11.2 seconds is 17.36035

Total total number of revolutions in the 21.9 second interval is 17.13806+17.36035 = 34.49841 = 35 revolutions

3 0

4 years ago