In outer space, where there is no gravity or air resistance, an astronaut pushes on two moon rocks, using 12N of force on each. One rock has a mass of 2 kg, the other has a mass of 4 kg. Which statements are true? (Mark all true statements)

A. Both rocks will push back at the astronaut with 12 N.
B. Since the astronaut is weightless, he cannot push on the rocks.
C. Since both rocks are weightless, they do not push back on the astronaut.
D. The 4 kg rock pushes back on the astronaut twice as hard as the 2 kg rock.
E. Since both rocks are weightless, they will have the same acceleration.

A. Both rocks will push back at the astronaut with 12 N.

Explanation:

According to 3 rd law of Laws of motion of Newton , there is equal and opposite reaction so both the rocks will exert the same force of 12N on the astronaut separately . Acceleration of both of them will not be equal because their masses are different.

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