Answer:
0.087 m
Explanation:
Length of the rod, L = 1.5 m
Let the mass of the rod is m and d is the distance between the pivot point and the centre of mass.
time period, T = 3 s
the formula for the time period of the pendulum is given by
.... (1)
where, I is the moment of inertia of the rod about the pivot point and g is the acceleration due to gravity.
Moment of inertia of the rod about the centre of mass, Ic = mL²/12
By using the parallel axis theorem, the moment of inertia of the rod about the pivot is
I = Ic + md²

Substituting the values in equation (1)


12d² -26.84 d + 2.25 = 0


d = 2.15 m , 0.087 m
d cannot be more than L/2, so the value of d is 0.087 m.
Thus, the distance between the pivot and the centre of mass of the rod is 0.087 m.
Answer:
a) t=10.2s
b) The 2g-cube moves first
Explanation:
Since the electric force is the same on both cubes and so is the coefficient of static friction, the first one to move will be the one with less mass.
So, on the 2g-cube the sum of forces are:

Replacing the friction on the first equation:
Thus 
The electric force is:
Solving for q:
q=71.44nC
This amount divided by the rate at which they are being charged:
t = 71.44nC / 7nC/s = 10.2s
This can be answered using the beat frequency formula, which is simply the difference between 2 frequencies.
Let: <span>fᵇ = beat frequency
</span>f₁ = first frequency
f₂ = second frequency
fᵇ = |f₁ - f₂|
substituting the values:
fᵇ = |24Hz - 20Hz|
fᵇ = 4Hz
The unit Hz also means beats per second, therefore:
<span>fᵇ = 4 beats per second
</span>
Therefore, the answer is C. 4
Answer:
Total charge flow through the cooker is 21600 C
Explanation:
As we know that the current flow through the cooker is given by Ohm's law
here it is given as




now the charge flow through it is given as

total time is t = 8 hours


Answer:
ΔLa/ΔLb = 1
Explanation:
The change in length of a solid is given by the following formula:
ΔL = α L ΔT
where,
ΔL = Change in length
α = coefficient of linear expansion
L = Original Length
ΔT = Change in Temperature
Since, the length and change in temperature for both rods are same. Also, the material of each rod is same, which implies that coefficient of linear expansion for both rods is same. Hence, the ratio of change in length of both rods will be:
<u>ΔLa/ΔLb = 1</u>