Answer:
i/f = i/o + i/i f = focal, o = object, i = image
1 / i = 1 / f - 1 / o = (o - f) / o f
i = o * f / ( o - f) image distance
i = 12.5 * 22 / (12.5 - 22) = -28.9 cm
Image is real
Image is 28.9 cm to left of lens
M = - i / o = = 28.9 / 12.5 = 2.3 magnification (convex lens)
Well 200 doubled or (x2)=400 if that’s what it means
Answer:
Explanation:
Given
mass of sphere 
diameter of sphere 
radius 

friction will provide resisting torque so
where 







(b)time taken to decrease its rotational speed by 



Answer:
The answer is explained below.
Explanation:
All the point on the disk has same angular acceleration. Here, the point P is at the midway between the center and the rim of the disk and the point Q is at rim of the disk.
So, the distance of the point Q from the axis is twicee the distance of the point P from the axis.
<em>Rp - R</em>
<em>Rq - 2R</em>
The linear acceleration is
α2 - Rα
So, the linear acceleration of Q is twice as great as the linear acceleration of P.
The speed of the particle when it is in the circular motion depends on the radius of the particle.
In this case, the speed of point Q is twice the speed of point P.