Edu/en/... with the normal line. See image opposite.
- Rotate the light source so it is pointing at the
10° angle, note To the normal. Measure the
light bouncing OFF the surface only and write
it in table 1.
anator...
PIZT
a plane...
Table 1
ee ima...
Angle of incidence
Angle of reflection
10°
20°
30°
40°
I
50°
60°

weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards

the old price per ounce is c/4.

the new price per ounce is c/3.6.

the ratio of the old price to the new one is

(c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . = 9/10 . . "nine tenths" in either form