Answer:
B - Velocity
Explanation:
Velocity definition: “The speed of something in a given direction.”
The velocity of pin B after rod AB has rotated through 90* is vb = 3.2549 m/s.
<h3>What is Potential and Kinetic energy?</h3>
Potential energy is the energy that is stored in any item or system as a result of its location or component arrangement. The environment outside of the object or system, such as air or height, has no impact on it. In contrast, kinetic energy refers to the energy of moving particles inside a system or an item.
mass of rod, mab = 2.4kg
mass of rod, mbc = 4kg
conservation of energy


potential energy at position 1,

V1 = 2.5 * 9.81 * 0.18 + 4 * 9.81 * 0.18
V1 = 11.30112
kinetic energy T1 at position 1 is zero
potential energy at position 2 is zero
K.E at position 2,


= 1/3 *4 * (0.36)²
=0.10368kg m²

= 1/12 *4 * (0.6)²
=0.12kg m²
on putting the values in above equation we get,
T₂ = 1.0667vb²
0 + 11.30112 = 1.0667vb² + 0
vb = 3.2549 m/s
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Energy resources that cannot be replaced are called "non-renewable" energy resources.
Explanation:
In the given situation two forces are working. These are:
1) Electric force (acting in the downward direction) = qE
2) weight (acting in the downward direction) = mg
Therefore, work done by all the forces = change in kinetic energy
Hence,
It is known that the weight of electron is far less compared to electric force. Therefore, we can neglect the weight and the above equation will be as follows.

v = 
= 592999 m/s
Since, the electron is travelling downwards it means that it looses the potential energy.