n-type semiconductor is :
Which of the following is true about the charge acquired by P-type semiconductors ?
(a) Positive (b) Neutral
(c) Negative (d) Depends on concentration of p impurity
One of the following does not apply to a concave mirror. This is : (a) focal length is negative (b) image distance can be positive or negative (c) image distance is always positive (d) height of image can be positive or negative