Answer:
∑ τ =0, L₀ = 
Explanation:
In a circular turning movement, when the arms are extended and then contracted in two possibilities:
- They are lowered the force of gravity is what pulls them, the tension of the muscle becomes zero to allow this movement.
In this movement the force is vertical(gravity) and the movement of the center of mass of each arm is vertical, so that the work is the weight value of the arm by the distance traveled by the center of mass.
- Another possibility is that the arms have stuck to the body, in this case the person's muscles perform the force, this force is horizontal and the displacement is the horizontal of the center of mass of the arms from the extended position to the contracted
In these movements the torque of the external force is equal for each arm, but in the opposite direction, so they are canceled where a net torque of zero, this causes the angular momentum to be preserved, which changes is the moment of inertia of the system and therefore you must also change the angular velocity to keep your product constant
∑ τ =0
L₀ = 
I₀ w₀ = I w
Answer:
20 [N], in the opposite direction of the first force.
Explanation:
We know that newton's second law stipulates that the sum of forces on a body must be equal to the product of mass by acceleration.
![SumF = m*a\\30 + F = 2*5\\F = 30 - (2*5)\\F = - 20 [N]](https://tex.z-dn.net/?f=SumF%20%3D%20m%2Aa%5C%5C30%20%2B%20F%20%3D%202%2A5%5C%5CF%20%3D%2030%20-%20%282%2A5%29%5C%5CF%20%3D%20-%2020%20%5BN%5D)
The negative sign means that the other force acting on the body must be in the opposite direction to the force of 30 [N]
The dependent variable is: <em>"number of vocabulary words subjects can remember"</em>
<h3>
Which is the dependent variable?</h3>
In an experiment, we basically see how changing one variable affects another variable.
In this case, the experiment is:
<em>" if sleep affects the number of vocabulary words subjects can remember."</em>
Then the hours of sleep would be the independent variable (the one that the scientist can change) and the number of vocabulary words subjects can remember is the dependent variable (that depends on the independent variable).
So the correct answer is:
<em>"number of vocabulary words subjects can remember"</em>
If you want to learn more about variables:
brainly.com/question/15246027
#SPJ1
Answer:
Explanation:
We define the linear density of charge as:

Where L is the rod's length, in this case the semicircle's length L = πr
The potential created at the center by an differential element of charge is:

where k is the coulomb's constant
r is the distance from dq to center of the circle
Thus.

Potential at the center of the semicircle
Answer:
24cm/s
Explanation:
A=L*w
A'=L'*w'
L=13
w=5
L'=4
w'=6
A=?
A'=?
A=L*w
A=13*5
A=65
A'=L'*w'
A'=4*6
A'=24
*the given lengths are just to throw you off*