Physics for IGCSE & O level - Forces And Motion (Section 8)

• 1

  What does the term 'dynamic friction' refer to?

  回答

  (C)

  Friction that occurs when an object is in motion.
• 2

  What direction do the forces act, according to Newton's third law?

  回答

  (B)

  In opposite directions on different objects
• 3

  Which of the following relates to work done on an object?

  回答

  (B)

  When the object moves in the same direction as the force.
• 4

  What happens to an object's acceleration if the net force acting on it doubles?

  回答

  (B)

  The acceleration doubles.
• 5

  If an object has constant speed, what is the acceleration?

  回答

  (A)

  Zero
• 6

  What happens to the air resistance as the speed of a skydiver increases?

  回答

  (C)

  Air resistance increases.
• 7

  What is the relationship between force, mass, and acceleration?

  回答

  (B)

  Force = Mass * Acceleration
• 8

  If a car is traveling at 15 m/s for 10 seconds, what distance does it cover?

  回答

  (B)

  150 m
• 9

  What does the slope represent in a distance-time graph?

  回答

  (A)

  Speed
• 10

  What does the text say about using the gradient in a distance-time graph?

  回答

  (C)

  It tells you how much extra distance is covered in a period of time
• 11

  When air resistance equals the force of gravity on a falling object, what is the resulting velocity?

  回答

  (C)

  Constant
• 12

  What is the relationship between force and acceleration?

  回答

  (C)

  Force causes acceleration.
• 13

  Which factor(s) influence the magnitude of centripetal force?

  回答

  A

  B

  C
• 14

  Which of the following is the formula for Newton's Second Law of Motion?

  回答

  (B)

  F = ma
• 15

  Which term is best described as the opposition to the motion of the object?

  回答

  (D)

  Friction
• 16

  What happens to the momentum of a system when there are no external forces acting upon it?

  回答

  (D)

  It remains constant.
• 17

  In a speed time graph, what does a straight line parallel to the time axis indicate?

  回答

  (C)

  Object is moving at a constant speed.
• 18

  If the net force on an object is zero, what will be its state of motion?

  回答

  (C)

  It will move at a constant velocity or remain at rest.
• 19

  What is the effect of doubling the velocity of an object on its kinetic energy?

  回答

  (B)

  It quadruples.
• 20

  What does a curved line in a speed-time graph indicate?

  回答

  (C)

  Non-uniform acceleration.
• 21

  What is Newton's third law of motion?

  回答

  (A)

  For every action, there is an equal and opposite reaction.
• 22

  What happens to the weight of an object if you move it to a location with a lower gravitational field strength?

  回答

  (C)

  The weight decreases.
• 23

  What is an example of a situation where friction is desirable?

  回答

  (C)

  Walking on a sidewalk.
• 24

  What is the relationship between force and acceleration?

  回答

  (B)

  Force causes acceleration.
• 25

  What happens to the acceleration of an object if you double the net force acting on it, assuming the mass remains constant?

  回答

  (C)

  The acceleration doubles.
• 26

  Which of the following is the SI unit for acceleration?

  回答

  (A)

  m/s²
• 27

  Which quantities are considered as scalars?

  回答

  (A)

  Distance and time
• 28

  What does a decreasing velocity mean?

  回答

  (B)

  The object's speed is decreasing.
• 29

  What is the formula for calculating weight?

  回答

  (B)

  Weight = mass * acceleration
• 30

  Which of the following statements is true about weight?

  回答

  (B)

  Weight is the force of gravity acting on an object.
• 31

  What is the reaction force if an athlete pushes off the ground to jump?

  回答

  (B)

  The ground pushing the athlete upwards.
• 32

  What is the relationship between mass and inertia?

  回答

  (D)

  Mass is a measure of inertia.
• 33

  On a speed-time graph, a line with a negative slope indicates what?

  回答

  (C)

  Negative acceleration (deceleration).
• 34

  If a car's average speed is 30 m/s, how far does it travel in 2 minutes (120 seconds)?

  回答

  (C)

  3600 m
• 35

  What is the formula for acceleration?

  回答

  (B)

  a = (v_f - v_i) / t
• 36

  What is the acceleration of a free-falling object near the Earth's surface?

  回答

  (A)

  9.8 m/s²
• 37

  What is the action force when a person pushes a box across the floor?

  回答

  (C)

  The force of the person on the box.
• 38

  Which of the following is a unit of impulse?

  回答

  (B)

  kg m/s
• 39

  If the radius of a circle is doubled, while keeping the speed and mass constant, how does the centripetal force change?

  回答

  (B)

  It halves.
• 40

  What do we call the movement along a straight line?

  回答

  (C)

  Linear motion.
• 41

  Which of these statements are true about force?

  回答

  A

  B

  C
• 42

  If you push a box with a force of 10 N, and friction exerts a force of 3 N, what is the net force on the box?

  回答

  (B)

  7 N
• 43

  If the forces on an object are unbalanced, the object will:

  回答

  (B)

  Accelerate.
• 44

  In the experiment to measure 'g' on the moon, what factors are involved?

  回答

  A

  B
• 45

  What is dynamic friction?

  回答

  (B)

  Friction between surfaces in motion.
• 46

  What can you determine from a speed-time graph?

  回答

  A

  B

  C
• 47

  Which are correct statements about the distance-time graph?

  回答

  B

  C
• 48

  Which of the following are examples of forces?

  回答

  A

  C
• 49

  What is the relationship between the centripetal force and the mass of an object moving in a circle?

  回答

  (D)

  The centripetal force increases as the mass increases.
• 50

  What happens to an object's kinetic energy when it accelerates?

  回答

  (B)

  It increases.