Answer:
50 J
Explanation:
The net force acting on the box is given by the algebraic sum of the two forces, so:

The net work done on the box is equal to (assuming the net force is parallel to the displacement of the object)

where
F = 5 N is the net force on the object
d = 10 m is the displacement of the object
Substituting,

Kinetic energy means movement. This means that the more something moves, the more kinetic energy it will have! And the faster something moves, the more heat it produces! Altogether, this means that the more Kinetic energy something has, the hotter it will be!
The opposite is also true. The less something moves, it will have less Kinetic energy and the colder it will get.
If you're having trouble understanding this, think of it like how the particles in water move compared to how the particles in ice move. The particles in water are free flowing and can move wherever they want. If they get colder, they won't move as much, and eventually they'll stop flowing around, forming a solid and staying colder than the water will get.
Answer:
B
Explanation:
Two atoms which are isotopes of one another must have a different number of neutrons.
Isotopes are defined as atoms of the same element which have the same numbers of protons i.e. atomic number remains the same, but has different numbers of neutrons. It is observed that they have same chemical properties due to the same electronic configuration but physical properties differs.
Answer:
(b) Yes, the earth gains momentum but the change in momentum of the earth is much lesser compared to that of everyone in the air. The resistance to motion (inertia of the earth), which is a function of its mass is so great that the earth's acceleration is small in the given time frame.
Explanation:
From Newton's second law which can be stated mathematically as
F = m(v-u)/t = ma.
By Newton's law of gravitation, there is a force between the earth and everyone in the air. This force is responsible for the change in momentum of everyone in the air and this force gives them an acceleration equal to g = 9.80m/s². By Newton's law of gravitation and Newton's third law of motion, this force is also equal to the force exerted by everyone on the earth.
For this to be true,
F = M (everyone) ×a (everyone) = M(earth) × a (earth).
And
a (earth) = {M (everyone) ×a (everyone) }/M (earth)
Then
a (earth) must be lesser than a (everyone) since M(earth) >> M(everyone).
a = change in momentum/ time
Therefore the earth will have a much lesser change in momentum which is the reason we won't notice the earth's movement.
Thank you for reading.
Answer:
1)
a) f = 1m × 2 × (5A / √2) × (5A / √2) / 0.003m = 0.00166... (66 is repeating)
b) The currents on two wires on a AC chord are always moving in opposite direction and so they are always replusing.
c) There needs to be a sheath to dampen the replusing, fluctuating force of the wires.
2)
a) v = √( ( (-2)(-1.6 × 10^(-16))(3000V) ) / (2.84 × 10^(-20)kg) ) = 5.81227 × 10^3
b) Any ion transversing a chamber having a magnetic field will deflect.
c) The direction of the electric field is vertical because it's perpendicular to the plates. The electric field magnitude is independent from the magnitude of the magnetic field and charge. So it's not possible to find the magnitude of the electric field, without knowing the voltage on the plates, the distance between the plates, and the dielectric constant.
d) Assuming the mangetic field remained, the path of the negative ions will be deflected vertically given that the magnetic field is horizontally perpendicular to the negative charged ions movement.
Sorry it took so long :) If anything is incorrect please let me know.