Answer:
E.true only when no charge is enclosed within the Gaussian surface.
Explanation:
Because Gauss’s law states that the net flux of an electric field in a closed surface is directly proportional to the enclosed electric charge.
Answer:
Earth would continue moving by uniform motion, with constant velocity, in a straight line
Explanation:
The question can be answered by using Newton's first law of motion, also known as law of inertia, which states that:
"an object keeps its state of rest or of uniform motion in a straight line unless acted upon by an external net force different from zero"
This means that if there are no forces acting on an object, the object stays at rest (if it was not moving previously) or it continues moving with same velocity (if it was already moving) in a straight line.
In this problem, the Earth is initially moving around the Sun, with a certain tangential velocity v. When the Sun disappears, the force of gravity that was keeping the Earth in circular motion disappears too: therefore, there are no more forces acting on the Earth, and so by the 1st law of Newton, the Earth will continue moving with same velocity v in a straight line.
The velocity of Ned as measured by Pam is the interpretation of v.
Answer: Option D
<u>Explanation:</u>
According to question, we know that this is an issue depending on the logical and translation of the factors. From the measured information taken what is gathered by the two people is communicated and we have given as:
The Ned reference framework : (x, t)
The Pam reference framework : 
From the reference framework, we realize that ν is the speed of Pam (the other reference framework) as estimation by Ned.
At that point, 
is the speed of Ned (from the other arrangement of the reference) as estimation by Pam.
Answer: A. Greater than 384 Hz
Explanation:
The velocity of sound is directly related to the temperature rather it is directly proportional meaning if the temperature decreases the velocity decreases and if temperature increases the velocity increases.
Now, we are given that temperature has risen from 20°C to 25°C meaning it has increases. So it implies that velocity must also increase.
Also, the velocity for organ pipe is directly proportional to its frequency. Now if velocity increases frequency must also increase. In this case, the original frequency is 384 Hz. Now increasing the temperature resulted in increase in velocity and thus increase in frequency.
So option a is correct. i.e. now frequency will be greater than 384 Hz.
We want to know the amount of force that stretches the spring 0.22 m.
That force is the WEIGHT of the mass hung from it.
The weight of the mass is (mass) times (gravity).
To do that calculation, we need to know the value of gravity, but
gravity has different values on every planet. I shall assume that
this whole springy question is taking place on Earth, so that the
value of gravity is 9.8 m/s² .
The weight of the mass is (0.4 kg) x (9.8 m/s²) = 3.92 Newtons.
The spring constant is
(force/length of the stretch)
= (3.92 Newtons) / (0.22 meters)
= (3.92 / 0.22) Newtons/meter
= 17.82 N/m .
