Final answer:
The claim that forklifts cannot tip backwards is false, and the statement about pushing a box with exactly 100 N force up a ramp is also false, as the required force depends on multiple factors including ramp angle and friction. The correct answer is option 2.
Step-by-step explanation:
The statement that because the forklifts are designed with the forks in front, it is not possible for it to tip backwards is false. Forklifts can indeed tip backwards if they are operated improperly, such as when they're carrying a load that's too heavy or when they are driven too quickly in reverse. It's important for forklift operators to understand how the center of gravity works and to adhere to safety guidelines in order to prevent accidents.
As for the physics problem about the ramp: the statement is false. The boy pushing a box up a ramp does not necessarily exert a force of exactly 100 N. The actual force he needs to exert depends on several factors, including the angle of the incline and the friction between the box and the ramp. The work done against gravity (potentially 300 N × 1.0 m for vertical displacement) doesn't directly translate into the force needed along the ramp, because the ramp reduces the effective force needed to lift the box due to its mechanical advantage.