Electromagnetic waves are those waves that are composed of electric and magnetic fields perpendicular to each other and to the direction of the propagation. All electromagnetic waves have the same speed.
That is, 3×10⁸ m/s.
X-ray is one of the electromagnetic waves. So are light, gamma rays, and radio waves.
Thus the speed of all these waves is equal.
Thus, the correct answer is option C, "Same as speed of radio waves"
Answer
A) Positively charged two insulating rod are brought closed to an object they repel each other. It means the Object is positively charged. Because similar charge repel each other.
The correct answer is Option A.
B) we know force between to charges is calculated using Formula
.......(1)
form the given condition in the question



from equation (1)

hence, the correct answer is Option C.
Answer:
Free-fall is defined as the movement where the only force acting on an object is the gravitational force.
By the second Newton's law, we have that:
F = m*a
Where F = Force, m = mass, a = acceleration.
We can write this as:
a = F/m
And the gravitational force can be written as:
F = (G*M/r^2)*m
Where G is the gravitational constant, M is the mass of the Earth in this case, and r is the distance between both objects (the center of the Earth and the free-falling object)
As the radius of the Earth is really big, the term inside the parentheses is almost constant in the region of interest, then we can write:
G*M/r^2 ≈ g
And the gravitational force is:
F = g*m
And by the second Newton's law we had:
a = F/m = (g*m)/m = g
a = g
Then the acceleration does not depend on the mass of the object.
Then the thing that is common among the free-falling objects is the vertical acceleration.
Answer:
a) T = 2.26 N, b) v = 1.68 m / s
Explanation:
We use Newton's second law
Let's set a reference system where the x-axis is radial and the y-axis is vertical, let's decompose the tension of the string
sin 30 =
cos 30 =
Tₓ = T sin 30
T_y = T cos 30
Y axis
T_y -W = 0
T cos 30 = mg (1)
X axis
Tₓ = m a
they relate it is centripetal
a = v² / r
we substitute
T sin 30 = m
(2)
a) we substitute in 1
T =
T =
T = 2.26 N
b) from equation 2
v² =
If we know the length of the string
sin 30 = r / L
r = L sin 30
we substitute
v² =
v² =
For the problem let us take L = 1 m
let's calculate
v =
v = 1.68 m / s
Answer:
110
Explanation:
to find neutrons we have to subtract the atomic number from the atomic mass.
atomic mass = 183.84
atomic no = 74
183.84 - 74 = 109.84
round off = 110