CIE iGCSE Co-Ordinated Science P1.5.1 Effects of forces Exam Style Questions Paper 1
Question
Which statement applies to a system in equilibrium?
A. There is a resultant force and there is a resultant turning effect on the system.
B. There is a resultant force but there is no resultant turning effect on the system.
C. There is no resultant force but there is a resultant turning effect on the system.
D. There is no resultant force and there is no resultant turning effect on the system.
▶️Answer/Explanation
Answer: D
Explanation: In equilibrium, there is no resultant force and no resultant turning effect (moment) acting on the system.
Question
The diagram shows a large force of magnitude P and a small force of magnitude Q acting on a box.
Which expression gives the magnitude of the resultant force on the box?
A P + Q
B P – Q
C P × Q
D P ÷ Q
▶️Answer/Explanation
Answer: B. P – Q
Explanation: The resultant force is the difference between the two forces since they are acting in opposite directions. Therefore, the magnitude of the resultant force is P – Q.
Question
The diagrams show the two forces acting on four objects P, Q, R and S.
Which two objects experience equal resultant forces acting in the same direction?
A P and Q B P and R C Q and R D Q and S
▶️Answer/Explanation
Ans :A
Question
The diagrams show the only forces acting on four moving objects.
Which object is travelling at constant speed?
▶️Answer/Explanation
Ans 😀
Question
An object is travelling at constant speed in a straight line. There is no resultant force on the object.
What happens to the object?
(A) It continues at constant speed but changes direction.
(B) It continues at constant speed in the same direction.
(C) Its speed decreases but it continues in the same direction.
(D) Its speed increases but it continues in the same direction.
▶️Answer/Explanation
Ans: B
Question
Two children X and Y pull on a rope in opposite directions.
The diagram shows the size of each force and its direction.
What is the resultant force on the rope?
A 50 N towards X
B 50 N towards Y
C 950 N towards X
D 950 N towards Y
▶️Answer/Explanation
Ans : A
Question
The diagrams show all the forces acting on each of four objects.
Which object is not in equilibrium?
▶️Answer/Explanation
Ans : D
Question
The diagrams show four objects, each acted on by only two forces.
Which object is in equilibrium?
▶️Answer/Explanation
Ans: D
Question
A train travels along a horizontal track at constant speed. Two of the forces acting on the train are shown.
A force of air resistance is also acting on the train to give it a resultant force of zero.
What is this air resistance force?
(A) 40 000N backwards
(B) 80 000N backwards
(C) 40 000N forwards
(D) 80 000N forwards
▶Answer/Explanation
Ans : A
Question
The diagrams show all the forces acting on three objects, X, Y and Z .
Which of the objects experience a resultant force?
(A) X, Y and Z (B) X only (C) Y and Z only (D) Y only
▶️Answer/Explanation
Ans: C
Question
Which statement about a resultant force is correct?
(A) An object must have a resultant force acting on it if it is moving.
(B) An object must have a resultant force acting on it if it is slowing down.
(C) Two forces must be in the same direction to produce a resultant force.
(D) Two forces must have the same magnitude to produce a resultant force.
▶️Answer/Explanation
Ans: B
Question
The diagram shows the two forces acting on a skydiver.
What is the resultant force on the skydiver?
A) 400 N downwards
B) 400 N upwards
C) 1000 N downwards
D) 1000 N upwards
▶️Answer/Explanation
Answer: A) 400 N downwards
Explanation: The resultant force is calculated by subtracting the smaller force (air resistance, 600 N) from the larger force (weight, 1000 N): \[ \text{Resultant force} = 1000\, \text{N} – 600\, \text{N} = 400\, \text{N} \text{ downwards} \]
Question
The diagram shows two teams P and Q pulling on a rope. Team P pulls with a force of 500 N to the left and team Q pulls with a force of 800 N to the right.
What is the resultant force acting on the middle of the rope?
A. \( 300 \, \text{N} \) to the left
B. \( 300 \, \text{N} \) to the right
C. \( 1300 \, \text{N} \) to the left
D. \( 1300 \, \text{N} \) to the right
▶️Answer/Explanation
Answer: B
Explanation: The resultant force is the difference between the two forces since they are acting in opposite directions. Resultant force = 800 N – 500 N = 300 N to the right.
Question
Two children X and Y pull on a rope in opposite directions.
The diagram shows the size of each force and its direction.
What is the resultant force on the rope?
A. 50 N towards X
B. 50 N towards Y
C. 950 N towards X
D. 950 N towards Y
▶️Answer/Explanation
Answer: A. 50 N towards X
Explanation: The resultant force is calculated by subtracting the smaller force from the larger force. If X pulls with 500 N and Y pulls with 450 N, the resultant force is \( 500 \, \text{N} – 450 \, \text{N} = 50 \, \text{N} \) towards X.
Question
What cannot be changed by a force acting on a body?
A. the mass of the body
B. the motion of the body
C. the shape of the body
D. the size of the body
▶️Answer/Explanation
Answer: A. the mass of the body
Explanation: A force can change the motion, shape, or size of a body, but it cannot change the mass of the body. Mass is an intrinsic property of matter and is not affected by external forces.
Question
There is no resultant force acting on a body. Which statement is correct?
A The body is either at rest or moving at constant speed in a straight line.
B The body must be at rest.
C The body is gaining speed.
D The body is losing speed.
▶️Answer/Explanation
Answer: A
Explanation: If there is no resultant force, the body will either remain at rest or continue to move at a constant speed in a straight line (Newton’s First Law of Motion).