Photo AI
1. Figure 1 shows some forces acting on a seesaw - Edexcel - GCSE Physics - Question 1 - 2020 - Paper 1
Question 1
1. Figure 1 shows some forces acting on a seesaw. The forces shown have the same magnitude but act in different directions. In which of these could the forces acting... show full transcript
Worked Solution & Example Answer:1. Figure 1 shows some forces acting on a seesaw - Edexcel - GCSE Physics - Question 1 - 2020 - Paper 1
Step 1
In which of these could the forces acting on a seesaw be in equilibrium?
Answer
To determine which set of forces could lead to equilibrium on a seesaw, the forces must be equal in magnitude and opposite in direction. Looking at the options:
- A: Not in equilibrium as the forces act in the same direction.
- B: In equilibrium since the upward and downward forces are equal and opposite.
- C: Not in equilibrium as the forces act in the same direction.
- D: In equilibrium as the forces act in opposite directions and are equal.
Therefore, options B and D could represent forces acting in equilibrium.
Step 2
Explain why it is easier to close the door by pushing at point P rather than pushing at point Q.
Answer
It is easier to close the door by pushing at point P rather than at point Q due to the concept of leverage. The force applied at point P is further from the hinges than at point Q, resulting in a larger moment (torque) produced by the same force. The moment is calculated as the product of the force and the distance from the pivot (hinge). Thus, pushing at point P requires less force to achieve the same rotational effect compared to pushing at point Q.
Step 3
Calculate the force F2 by taking moments about A.
Answer
To find the force F2, we can use the condition for rotational equilibrium, which states that the sum of the clockwise moments about any hinge must equal the sum of the counterclockwise moments.
-
The person's weight (450 N) creates a moment around point A at a distance of 0.50 m.
- Moment = Force x Distance = 450 N x 0.50 m = 225 Nm (clockwise).
-
The upward force F2 acts at the distance of 0.80 m from point A.
- Moment due to F2 = F2 x 0.80 m (counterclockwise).
Setting the moments equal gives:
- Solving for F2: F2 = rac{225}{0.80} = 281.25 N
Thus, the force F2 is approximately 281.25 N.