A:True because Lithium is the lighest solid and metal and the third lightest element.
Answer:
a) The rotational inertia when it passes through the midpoints of opposite sides and lies in the plane of the square is 16.8 kg m²
b) I = 50.39 kg m²
c) I = 16.8 kg m²
Explanation:
a) Given data:
m = 0.98 kg
a = 4.14 * 4.14
The moment of inertia is:

For 4 particles:

b) Distance from top left mass = x = a/2
Distance from bottom left mass = x = a/2
Distance from top right mass = x = √5 (a/2)
The total moment of inertia is:

c)

Our values can be defined like this,



The problem can be solved for part A, through the Work Theorem that says the following,

Where
KE = Kinetic energy,
Given things like that and replacing we have that the work is given by
W = Fd
and kinetic energy by

So,

Clearing F,

Replacing the values


B) The work done by the wall is zero since there was no displacement of the wall, that is d = 0.
1 meter = 1e9 nm
To get meters, divide nanometers by 1e9: 9.95nm / 1x10^9 = 9.95x10^-9 meters
Answer: 9.95e-9 meters
Answer:
T1 = 130N, T2 = 370N
Explanation:
In order for the system to be at rest, the sum of all forces must be zero and the torque around a point on the beam must be zero.
1. forces:
Let tension in rope 1 be T1 and in rope 2 be T2:
ma = T1 + T2 - 100N - 400N = 0
(1) T1 + T2 = 500N
2. torque around the center point of the beam:
τ = r x F = 5*T1 + 3*400N - 5*T2 = 0
(2) T1 - T2 = -240N
Solving both equations:
T1 = 130N
T2 = 370N