Answer:
The resistance must be 6.67
Solution:
Resistance, 
Resistance, 
For the current to be the same when the switch is open or closed, the resistances must be connected in parallel as current is distributed in parallel with the same voltage across the circuit:
Thus in parallel:



Answer:
twice
Explanation:
From magnification = height of image / height of object
Distance of image/ distance of object = magnification
If the distance and height of the object represents the initial light distance and the exposed surface respectively.
And similarly the distance and height of the image represents the final light distance and the exposed surface respectively.
Hence the new image exposure would be twice as large.
If we use the formula our point of investigation is Height of image,
H2= D2/D1× H1
H2 = 2D2/D1 × H1
H2 = 2H1
Answer:
α = 395 rad/s²
Explanation:
Main features of uniformly accelerated circular motion
A body performs a uniformly accelerated circular motion when its trajectory is a circle and its angular acceleration is constant (α = cte). In it the velocity vector is tangent at each point to the trajectory and, in addition, its magnitude varies uniformly.
There is tangential acceleration (at) and is constant.
at = α*R Formula (1)
where
α is the angular acceleration
R is the radius of the circular path
There is normal or centripetal acceleration that determines the change in direction of the velocity vector.
Data
R = 0.0600 m :blade radius
at = 23.7 m/s² : tangential acceleration of the blades
Angular acceleration of the blades (α)
We replace data in the formula (1)
at = α*R
23.7 = α*(0.06)
α = (23.7) / (0.06)
α = 395 rad/s²