The picture shows rays passing through an unknown lens. A grey rectangle with rounded corners labeled Unknown lens has a focal point to its left and a grey arrow to the left of the focal point, pointing up from a line running through the center of the lens. A line from the top of the grey arrow goes straight to the centerline of the lens and then sharply down and right to focal point B. A line from the top of the grey arrow goes shallowly down and right to the centerline of the lens and then straight right to label A. A line from the top of the grey arrow goes straight down and right through the center of the lens to a label D. A line from the top of the grey arrow goes down and right through the left focal point to the centerline of the lens and then straight to a label C. Which ray would appear on a ray diagram for both a concave lens and a convex lens? A B C D

b

explanation:

bc its just b

force is based upon mass and acceleration.the statement is not always true.

it can be explained from newton's second law of motion.

as per newton's second law of motion the rate of change of momentum is directly proportional to the applied force and takes place along the direction of force.

mathematically it can be written as -

                                              ⇒      

here   k is the proportionality constant whose value is 1.

                                                            [a is the acceleration=dv/dt]

hence we see that force not only depends on mass and acceleration but also on velocity and rate of change of mass. force f will depend on mass and acceleration only when mass is constant.

hence the statement that force is based upon mass and acceleration is false.

friction

explanation:

they us to move forward and backwards

96.77 amp

explanation:

rl = 250/100 = 2.5 ohms.

egl = 250 + (100 × 0.1) + 2 = 262 v.

at 700 r.p.m., eg2 = 262 × 700/1000 = 183.4 v.

if ia is the new current, then eg2 - 2 - (ia × 0.1) = 2.5 ia

which means this will give ia = 96.77 amp.