In a double-slit experiment using monochromatic light, a screen is placed 1.20 m away from the slits, which have a separation distance of 0.0240 mm . The position of the third-order maximum is 6.75 cm from the center of the central maximum. Required:
Find the wavelength of the light.

ok

explanation:

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

statement #3 on andre"s list is false.