Syllabus Edition

First teaching 2014

Last exams 2024

|

Forces (DP IB Physics: SL)

Exam Questions

3 hours45 questions
1
Sme Calculator
1 mark

A ladder rests on a rough wall and rough horizontal ground. Which diagram correctly labels all forces acting on the ladder? 

2-2-q1-sl-easy-mcq-phy

    Did this page help you?

    2
    Sme Calculator
    1 mark

    A parachutist of mass 75 kg is falling vertically through the air at a constant speed of 0.6 m s–1

    What is the resultant force on the parachutist? 

    • 0 N

    • 75 N

    • 750 N

    • 1000 N

    Did this page help you?

    3
    Sme Calculator
    1 mark

    Which statement best summarises Newton's Third Law of Motion? 

    • If object X exerts a force on object Y, then object Y exerts a greater and opposite force on object X

    • If object X exerts a force on object Y, then object Y exerts a lesser and opposite force on object X

    • If object X exerts a force on object Y, then object Y exerts an equal and opposite force on object X

    • If object X exerts a force on object Y, then object Y exerts no force on object X

    Did this page help you?

    4
    Sme Calculator
    1 mark

    The image shows a block resting on an inclined plane. 

    2-2-q4-sl-easy-mcq-phy

    Which row in the table gives the correct interpretation of the forces acting on the block, RF and W?

      R F W
    A. weight reaction static friction
    B. dynamic friction weight reaction
    C. reaction dynamic friction weight
    D. reaction static friction weight

      Did this page help you?

      5
      Sme Calculator
      1 mark

      Which statement about Newton's Second Law of Motion is true? 

      • For bodies of constant mass, the resultant force acting on it is inversely proportional to its acceleration

      • For bodies of a non-constant mass, the resultant force acting on it is proportional to its acceleration

      • For bodies of constant mass, the resultant force acting on it is proportional to its acceleration

      • For bodies of a non-constant mass, the resultant force acting on it is inversely proportional to its acceleration

      Did this page help you?

      6
      Sme Calculator
      1 mark

      Which of the following statements about friction is not true?

      • Friction always acts in the opposite direction to the direction of motion 

      • Static friction occurs when two solid objects are in contact and no movement occurs between the two objects

      • For a stationary object, the force due to the coefficient of dynamic friction is at a maximum

      • For a stationary object, the force due to the coefficient of dynamic friction is zero

      Did this page help you?

      7
      Sme Calculator
      1 mark

      Which statement best summarises Newton's first law of motion?

      • Whenever two objects interact the forces they exert on each other are opposite.

      • A resultant force on an object is equal to the rate of change in momentum.

      • A body will remain at rest or move with constant velocity unless acted on by a resultant force

      • A body will move in a constant velocity only if there is a resultant force acting upon it

      Did this page help you?

      8
      Sme Calculator
      1 mark

      Which statement about drawing free body diagrams is not correct?

      • Arrows must be drawn to scale and represent the size of the force involved

      • All force arrows must touch the object applying the force

      • Force arrows must be drawn as straight lines with a ruler

      • Force arrows don't have to be labelled

      Did this page help you?

      9
      Sme Calculator
      1 mark

      Which of the following equations for static friction is correct?

      • ma

      • Ff ≤ μsR

      • Ff  μdR

      • IΔt

      Did this page help you?

      10
      Sme Calculator
      1 mark

      Which statement is correct about the coefficient of friction, μ?

      • It is always between 0 and 1

      • The coefficient of friction can be different for the same material in different situations

      • The coefficient of dynamic and static friction between the same two surfaces will be different

      • The coefficient of dynamic friction is equal to the frictional force multiplied by the reaction force

      Did this page help you?

      1
      Sme Calculator
      1 mark

      A wooden block of weight W rests on a rough board that produces a friction force F. The end of the board is then raised up to angle θ until the block slides down the plane of the board at constant velocity v.

      q11_forces_ib-sl-physics-mcq

      Which row describes the forces acting on the block as it slides down the board?

       

      Frictional force on block

      Resultant force on block

      A.

      W sin θ

      0

      B.

      W cos θ

      W sin θF

      C.

      W cos θ

      0

      D.

      W sin θ

      FW sin θ

        Did this page help you?

        2
        Sme Calculator
        1 mark

        Which row gives the correct Newton’s third law force pair for a book on a table?

         

        Force A

        Force B

        A.

        Weight of the book

        Force of book on the table

        B.

        Gravitational force of the Earth pulling on the book

        Gravitational force of the book pulling on the Earth

        C.

        Weight of the book

        Reaction force from the table surface

        D.

        Gravitational force of the Earth pulling on the book

        Gravitational force of the table pulling on the Earth

          Did this page help you?

          3
          Sme Calculator
          1 mark

          An object of mass m is connected via a frictionless pulley to an object of mass M, where M > m. M rests on a horizontal rough surface with a frictional force f.q13_forces_ib-sl-physics-mcq

          What is the acceleration of the system?

          • 0

          • begin mathsize 16px style fraction numerator m g plus f over denominator open parentheses M plus m close parentheses end fraction end style

          • begin mathsize 16px style fraction numerator m g minus f over denominator open parentheses M plus m close parentheses end fraction end style

          • g

          Did this page help you?

          4
          Sme Calculator
          1 mark

          A photo hangs from two strings. It has a weight W and the two strings have equal tension T.

          What is the free–body diagram for this situation?

          q14_forces_ib-sl-physics-mcq

            Did this page help you?

            5
            Sme Calculator
            1 mark

            Which of the following are possible values for the maximum coefficient of static friction, size 16px mu subscript S and dynamic friction, begin mathsize 16px style mu subscript d end style?

               begin mathsize 16px style mu subscript S end style  mu subscript d
            A.

            0.012

            0.78

            B.

            0.35

            0.12

            C.

            1.50

            0.90

            D.

            0.26

            –0.77

              Did this page help you?

              6
              Sme Calculator
              1 mark

              A uniform ladder resting in equilibrium on rough ground leans against a smooth wall.

              Which diagram correctly shows the forces acting on the ladder?

              q16_forces_ib-sl-physics-mcq

                Did this page help you?

                7
                Sme Calculator
                1 mark

                A block of mass m rests on a trolley of mass M. The coefficient of dynamic friction between the block and the trolley is µ.

                q17_forces_ib-sl-physics-mcq

                A horizontal force F acts on the block causing it to slide over the trolley. What is the acceleration of the trolley?

                • fraction numerator F minus mu m g over denominator M end fraction

                • fraction numerator mu m g over denominator open parentheses M plus m close parentheses end fraction

                • fraction numerator F minus mu M g over denominator m end fraction

                • fraction numerator mu m g over denominator M end fraction

                Did this page help you?

                8
                Sme Calculator
                1 mark

                A sled with a child has a combined weight of 400 N and rests on a horizontal surface. The coefficient of static friction between the sled and the surface is 0.50 and the coefficient of dynamic friction is 0.30.

                A horizontal force F is applied to the sled and its magnitude increases uniformly from zero. Once the sled starts moving, the pulling force no longer increases.

                What is the minimum resultant force required on the moving sled?

                • 80 N

                • –80 N

                • 320 N

                • 0 N

                Did this page help you?

                9
                Sme Calculator
                1 mark

                Two coplanar forces of 11 N and 7 N act on an object. Which force could not be the resultant for these two forces?

                • 18 N

                • 1 N

                • 9 N

                • 4 N

                Did this page help you?

                10
                Sme Calculator
                1 mark

                Two boxes in contact are pushed in a line along a floor with a force F. The boxes are moving at a constant speed. Box X has a mass m and box Y has a mass 3m.q20_forces_ib-sl-physics-mcq

                What is the resultant force acting on Y?

                • F

                • F over 3

                • 3F

                • 0

                Did this page help you?

                1
                Sme Calculator
                1 mark

                A frictionless spring-operated latched is fitted to a door. 

                2-2-sl-mcq-hard-q1_1-phy

                When the latch is pushed in, the spring compresses.

                When the latch is released, which of the following best represents how acceleration a of the latch varies with the distance x it moves before stopping? 

                • 2-2-sl-mcq-hard-q1_2a-phy

                • 2-2-sl-mcq-hard-q1_2b-phy

                • 2-2-sl-mcq-hard-q1_2c-phy

                • 2-2-sl-mcq-hard-q1_2d-phy

                Did this page help you?

                2
                Sme Calculator
                1 mark

                Elaborate chandeliers can be modelled as layers of hanging bars. The diagram shows one such model with a mass m suspended from two bars of negligible mass, connected by five light strings. Each layer has N number of strings. 

                2-2-sl-mcq-hard-q2-phy

                Which expression gives the tension in any single string? 

                • fraction numerator m g over denominator N end fraction

                • fraction numerator m g over denominator N squared end fraction

                • N m g

                • left parenthesis N minus 1 right parenthesis m g

                Did this page help you?

                3
                Sme Calculator
                1 mark

                Two blocks, one made of wood and the other of iron, are arranged at rest on the ground. 

                2-2-sl-mcq-hard-q3-phy

                Which of the following statements is correct? 

                • The force exerted by the ground on the iron block in (1) is greater than the force exerted by the ground on the wooden block in (2) because the iron block, being denser than the wooden block, exerts more force on the ground. 

                • The force exerted by the wooden block on the iron block in (1) is equal to that exerted by the iron block on the wooden block in (2) by virtue of Newton's third law. 

                • The force exerted by the iron block on the wooden block in (1) is greater than that exerted by the wooden block on the iron block in (2). 

                • The force exerted by the wooden block on the iron block is equal to the weight of the wooden block in (1) while the force exerted by the iron block on the wooden block is equal to the weight of the iron block in (2). 

                Did this page help you?

                4
                Sme Calculator
                1 mark

                A child of mass m sits in a car seat which is accelerating horizontally at 0.2g, where g is the acceleration due to gravity. 

                What is the magnitude of the total force exerted by the car seat on the child? 

                • m g

                • square root of m g end root

                • square root of 0.2 end root m g

                • square root of 1.04 end root m g

                Did this page help you?

                5
                Sme Calculator
                1 mark

                The following scenarios describe specific types of motion: 

                1. A diver equipped so that they remain at constant depth below the water surface without any effort on their part
                2. An athlete clearing the bar in a high jump
                3. A parachutist descending at terminal velocity with the parachute fully open

                In which of the scenarios does the person concerned experience 'weightlessness'? 

                • I only 

                • II only 

                • II and III only

                • I, II and III

                Did this page help you?

                6
                Sme Calculator
                1 mark

                A pendulum bob hangs from the ceiling in a carriage in a train and is just above a certain mark on the floor when the train is at rest. When the train is moving with a constant velocity forward, which statement best outlines the position of the bob? 

                • The bob is behind the mark, so that the pendulum thread is along the resultant of the forces due to the motion of the train and gravity. 

                • The bob remains over the mark because the force due to the motion of the train is balanced by the reaction of the thread on the support. 

                • The bob oscillates about the mark because of the unbalanced force due to the motion of the train. 

                • The bob remains over the mark because the motion of the train produces no additional force on the bob. 

                Did this page help you?

                7
                Sme Calculator
                1 mark

                Two masses m and nm, where n > 1, are joined by a light string which passes over a frictionless pulley. The acceleration of free fall is g

                2-2-sl-mcq-hard-q7-phy

                What is the acceleration of the masses a and the tension in the string T

                 

                a

                T

                A.

                fraction numerator n minus 1 over denominator n plus 1 end fraction

                m g open parentheses fraction numerator n minus 1 over denominator n plus 1 end fraction close parentheses

                B.

                g left parenthesis n plus 1 right parenthesis

                m g open parentheses fraction numerator n minus 1 over denominator n plus 1 end fraction minus 1 close parentheses

                C.

                fraction numerator g left parenthesis n minus 1 right parenthesis over denominator n plus 1 end fraction

                m g open parentheses fraction numerator n minus 1 over denominator n plus 1 end fraction plus 1 close parentheses

                D.

                fraction numerator g left parenthesis n plus 1 right parenthesis over denominator n minus 1 end fraction

                m g open parentheses fraction numerator n plus 1 over denominator n minus 1 end fraction plus 1 close parentheses

                  Did this page help you?

                  8
                  Sme Calculator
                  1 mark

                  Two bodies, X and Y, having masses mX and mY respectively, exert forces on each other and have no external forces acting on them. The force acting on X is F, which gives X an acceleration aX.

                  What is the magnitude of the force on Y and its acceleration?

                   

                  Magnitude of force on Y

                  Acceleration of Y

                  A.

                  m subscript Y over m subscript X F

                  a

                  B.

                  F

                  m subscript Y over m subscript X a

                  C.

                  m subscript X over m subscript Y F

                  a

                  D.

                  F

                  m subscript X over m subscript Y a

                    Did this page help you?

                    9
                    Sme Calculator
                    1 mark

                    Two blocks with mass 5m and 3m are pushed along a smooth horizontal surface by an applied force F.

                    2-2-sl-mcq-hard-q9-phy

                    What is the magnitude of the force exerted between the blocks? 

                    • F

                    • 2 over 8 F

                    • 3 over 8 F

                    • 8 over 3 F

                    Did this page help you?

                    10
                    Sme Calculator
                    1 mark

                    Forces act in a variety of situations described below: 

                    1. The centripetal force holding a satellite in orbit round the Earth and the weight of the satellite 
                    2. Repulsive forces experienced by anti-parallel current-carrying conductors 
                    3. Attractive forces between two gas molecules passing close to each other
                    4. Attractive forces between the nucleus and orbiting electrons in an atom

                    Which of the situations describe pairs of forces as required by Newton's third law? 

                    • I and II only

                    • II and III only 

                    • I, II and IV only

                    • II, III and IV only

                    Did this page help you?