Atransparent photographic slide is placed in front of a converging lens with a focal length of 2.33 cm. an image of the slide is formed 13.0 cm from the slide. (a) how far is the lens from the slide if the image is real?

Explanation:

Let the slide be at a distance of u from lens . So the object distance is u.

Image distance  v = 13 - u .

Using lens formula

1/v -1/u = 1/f

1/ ( 13 - u) - 1 / u = 1 / 2.33

u - (13 - u )/u(13 -u ) = 1/2.33

2u - 13/ 13u - u² = 1/ 2.33

4.66 u - 30.29 = 13 u -u²

u² - 8.34 u - 30.29 = 0

u =  -2.73 cm

So lens will be at a distance of 2.73 cm  from the slide.

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.

find the surface area of the sphere to the nearest square unit. use a calculator.

a. 254 in.2

b. 64 in.2

c. 127 in.2

d. 1,018 in.2