Agirl pulls her younger brother on a sled along a flat sidewalk (the total mass of the sled is 30kg). a frictional force of 50n opposes the pull. when moving, the girl pulls on the sled with a force of 150n at an angle of 30 degrees.

how much time will it take for the sled to travel 50?

what is the normal force?

You want to move a heavy box with mass 30.0 kg across a carpeted floor. you pull hard on one of the edges of the box at an angle 30∘ above the horizontal with a force of magnitude 240 n, causing the box to move horizontally. the force of friction between the moving box and the floor has magnitude 41.5 n . what is the box's acceleration just after it begins to move