Answer:
Part a)

Part b)

Explanation:
As we know that the see saw bar is massless so here torque due to two masses is given as

here we will have

now we will have inertia of two masses given as

now we have

now the angular acceleration is given as

so we have

Part b)
Now if the rod is not massles then we will have total inertia given as

so we will have

now the acceleration is given as


Answer:
2. west
Explanation:
Given an electron is moving vertically upward from ground.
Now Fleming right hand rule state that: make L shape with thumb and index finger then point middle finger perpendicular to index and thumb.Then index finger points in the direction of moving charge , middle finger points in the direction of the magnetic field and thumb points in the direction of the magnetic force.
According to Fleming right hand rule the direction of the magnetic that acts on the electron is west.
0.36 J of work is done in stretching the spring from 15 cm to 18 cm.
To find the correct answer, we need to know about the work done to strech a string.
<h3>What is the work required to strech a string?</h3>
- Mathematically, the work done to strech a string is given as 1/2 ×K×x².
- K is the spring constant.
<h3>What will be the spring constant, if 40N force is required to hold a 10 cm to 15 cm streched spring?</h3>
- The force experienced by a streched spring is given as Kx. x is the length of the spring streched from its natural length.
- Then K = Force / x.
- Here x = 15 - 10 = 5 cm = 0.05 m
- K = 40/0.05 = 800N/m.
<h3>What will be the work required to strech that spring from 15 cm to 18 cm?</h3>
- Work done = 1/2×k×x²
- Here x= 18-15=3cm or 0.03 m
- So, W= 1/2×800×0.03² = 0.36 J.
Thus, we can conclude that the work done is 0.36 J.
Learn more about the spring force here:
brainly.com/question/14970750
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