A circuit has a current of 1.2 A. If the voltage decreases to one-third of its original amount while the resistance remains

A 0.500-kg block, starting at rest, slides down a 30.0° incline with static and kinetic friction coefficients of 0.350 and 0.250

Leviafan [203]

Answer:x=23.4 cm

Explanation:

Given

mass of block $m=0.5 kg$

inclination $\theta =30$

coefficient of static friction $\mu =0.35$

coefficient of kinetic friction $\mu _k=0.25$

distance traveled $d=77.3 cm$

spring constant $k=35 N/m$

work done by gravity+work done by friction=Energy stored in Spring

$mg\sin \theta d-\mu _kmg\cos \theta d=\frac{kx^2}{2}$

$mgd\left ( \sin \theta -\mu _k\cos \theta \right )=\frac{kx^2}{2}$

$0.5\times 9.8\times 0.773\left ( \sin 30-0.25\cos 30\right )=\frac{35\times x^2}{2}$

$x=\sqrt{\frac{2\times 0.5\times 9.8\times 0.773(\sin 30-0.25\times \cos 30)}{35}}$

$x=0.234 m$

$x=23.4 cm$

6 0

4 years ago

It is known that birds can detect the earth's magnetic field, but the mechanism of how they do this is not known. It has been su

san4es73 [151]

Answer:

$EMF = 5.01 \times 10^{-4} Volts$

Explanation:

Here we know that the EMF induced in this Field is given as

$EMF = vBL$

here B = perpendicular component of magnetic field

v = speed of the bird

L = length of the wings

now we have

$B = 5\times 10^{-5} sin40$

$v = 13 m/s$

$L = 1.2 m$

now we have

$EMF = (13)(3.21 \times 10^{-5})(1.2)$

$EMF = 5.01 \times 10^{-4} Volts$

8 0

3 years ago

Which best explains why a wood-burning fireplace represents an open system?

Alona [7]

The answer will be B

5 0

3 years ago

An automobile tire is rated to last for 35,000 miles. to an order of magnitude, through how many revolutions will it turn?

Furkat [3]

<span>The tire will rotate about 10 million times. An automobile tire is slightly less than 2 and half feet in diameter. It's circumference is that times pi with is a bit over 3. So 2.5 * 3 = 7.5 ft as an estimate for how far the tire rolls per revolution. A mile is a bit over 5000 feet, so call it 700 revolutions per mile. For the 35000 miles, call it 7 times 5000 miles. Now 7 times 7 is a bit under 50, so call 7 * 700 = 5000. And 5000 times 5000 = 25000000. The nearest order of magnitude is 10 million. So as an order of magnitude estimate, a automobile tire will rotate about 10 million times during it's life.</span>

7 0

3 years ago

Which one of the following scenarios accurately describes a condition in which resonance can occur? A. A column of air has a hei

Butoxors [25]

The correct option is B.
Resonance is said to occur when one object which is vibrating at the same natural frequency of a second object forces the second object into vibrational motion. When resonance is achieved a big loud voice is usually heard. Resonance generally requires three conditions to occur:
1. An object that has a natural frequency.
2. A force that is functioning at the same frequency as the natural frequency.
3. Prevention of energy loss.

4 0

3 years ago