Answer:
Option (D) : The object slows down.
Answer:
B. The current increases.
Explanation:
As we know that rate of flow of charge through the conductor is known as electric current
So we have

here we know that charge Q flowing through the conductor is constant while the time in which it passes through it is decreased
so we can say that the ratio of charge and time will increase
so here we have

So correct answer will be
B. The current increases.
Answer:
Explanation:
Let m be mass of each sphere and θ be angle, string makes with vertex in equilibrium.
Let T be tension in the hanging string
T cosθ = mg ( for balancing in vertical direction )
for balancing in horizontal direction
Tsinθ = F ( F is force of repulsion between two charges sphere)
Dividing the two equations
Tanθ = F / mg
tan17 = F / (7.1 x 10⁻³ x 9.8)
F = 21.27 x 10⁻³ N
if q be charge on each sphere , force of repulsion between the two
F = k q x q / r² ( r is distance between two sphere , r = 2 x .7 x sin17 = .41 m )
21.27 x 10⁻³ = (9 X 10⁹ x q²) / .41²
q² = .3973 x 10⁻¹²
q = .63 x 10⁻⁶ C
no of electrons required = q / charge on a single electron
= .63 x 10⁻⁶ / 1.6 x 10⁻¹⁹
= .39375 x 10¹³
3.9375 x 10¹² .
Answer:
They both have the same angular speed.
Explanation:
The mathematical formula for angular speed is:

where
is angular speed,
is a constant, and
is the period (the time it takes the marry-go-round to complete a lap).
What we can see from the formula is that, since the
does not change its value, the angular speed depends only on the period T.
In this case for both the children closer to the outher edge and for the children closer to the center, the time to complete a lap is the same, because the time does not depend on where they are sitting in the marry go round. This means that the period for both is the same.
Thus, since the period for both is the same, the angular speed given by
will also be the same
D is the correct answer!!