Forces and motion
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1.Which of the following is the SI unit of force?
Easy- Anewton
- Bjoule
- Cpascal
- Dkilogram
2.Force is a scalar quantity.
EasyTrue or false?
3.Which of the following is a non-contact force?
Easy- Afriction
- Btension
- Cgravitational force
- Dnormal force
4.An object is at rest on a table. Which of the following statements about the forces acting on it is correct?
Easy- AThe weight of the object is greater than the normal force.
- BThe weight of the object is less than the normal force.
- CThe weight and normal force are equal and opposite.
- DThere are no forces acting on the object.
5.Which of the following are vector quantities? (Select all that apply)
Medium- Aforce
- Bspeed
- Cvelocity
- Dmass
- Eacceleration
6.Arrange the following steps in the correct order to draw a force arrow diagram for a book resting on a table:
Easy- Draw a dot to represent the book.
- Draw an upward arrow from the dot labeled 'Normal force'.
- Draw a downward arrow from the dot labeled 'Weight'.
- Ensure the arrows are equal in length.
7.Match each simple machine to its description:
Easy- Lever
- Pulley
- Inclined plane
- A rigid bar that rotates around a fulcrum
- A wheel with a groove that a rope passes over
- A sloping surface used to raise objects
8.Which of the following is a vector quantity?
Easy- AMass
- BSpeed
- CForce
- DDistance
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9.Which of the following are contact forces? (Select all that apply)
Easy- AFriction
- BGravity
- CTension
- DNormal force
- EMagnetic force
10.An object at rest has no forces acting on it.
EasyTrue or false?
11.Match each simple machine to its description.
Easy- Lever
- Pulley
- Inclined plane
- A wheel with a groove that a rope passes over
- A rigid bar that pivots about a fulcrum
- A sloping surface used to raise objects
12.Arrange the following steps in the correct order to calculate the net force on an object when multiple forces act along the same line.
Medium- Assign a positive direction
- Add forces in the positive direction
- Subtract forces in the negative direction
- The result is the net force
13.Which of the following statements about Newton's first law is correct?
Easy- AAn object at rest will stay at rest unless acted on by an unbalanced force.
- BA force is required to keep an object moving at constant velocity.
- CAn object in motion will slow down unless a constant force is applied.
- DThe acceleration of an object is directly proportional to its mass.
14.A 2 kg mass is pulled along a horizontal surface with a force of 10 N. The frictional force opposing motion is 4 N. What is the acceleration of the mass?
Medium- A3 m/s²
- B5 m/s²
- C7 m/s²
- D2 m/s²
15.Which of the following graphs represents an object moving with constant non-zero velocity?
Medium- AA straight line with positive slope on a distance-time graph
- BA horizontal line on a distance-time graph
- CA curve increasing on a distance-time graph
- DA straight line with positive slope on a velocity-time graph
16.A student measures the time for a ball to fall from different heights. Which graph best shows the relationship between the height (h) and the time squared (t²)?
Medium- AA straight line through the origin
- BA curve decreasing
- CA horizontal line
- DA straight line with negative slope
17.Match each simple machine to its primary function:
Medium- Lever
- Pulley
- Inclined plane
- Changes direction of force
- Multiplies force using a pivot
- Reduces the force needed to lift an object by increasing distance
18.The force of gravity on an object is called weight and is measured in kilograms.
EasyTrue or false?
19.Which of the following statements about forces are correct? (Select all that apply)
Medium- AA force can change the shape of an object.
- BFriction always opposes motion.
- CThe SI unit of force is the kilogram.
- DForce is a vector quantity.
20.Arrange the following steps in the correct order to determine the net force on an object when forces act in opposite directions:
Medium- Assign a positive direction.
- Add forces in the positive direction.
- Subtract forces in the opposite direction.
- The result is the net force.
21.In an experiment to investigate the effect of net force on acceleration, a student pulls a trolley along a friction-compensated runway with a elastic cord. The acceleration is measured for different numbers of elastic cords (each providing the same force). Which of the following graphs best represents the expected relationship between acceleration and the number of cords?
Medium- AA straight line through the origin with positive slope
- BA horizontal straight line
- CA curve that flattens off at high numbers of cords
- DA straight line with negative slope
22.A student sets up an experiment to measure the friction between a wooden block and a table surface. She pulls the block with a spring balance at constant speed and records the force. Which of the following changes would cause the recorded force to increase?
Medium- AUsing a smoother table surface
- BAdding more mass on top of the block
- CPulling the block faster
- DUsing a lighter block
23.In an experiment to investigate the relationship between mass and acceleration for a constant net force, a student uses a dynamics cart on a friction-compensated track. Which of the following procedures are appropriate for this experiment? (Select all that apply)
Medium- AAdding masses to the cart to change its mass
- BUsing a spring scale to measure the net force
- CRecording the time for the cart to travel a fixed distance
- DReleasing the cart from rest each time
- EUsing a ticker timer or motion sensor to measure acceleration
24.In a friction-compensated experiment, if the net force on an object is doubled, the acceleration is halved.
EasyTrue or false?
25.Match each experimental measurement technique to the quantity it directly measures.
Medium- Ticker timer
- Motion sensor
- Spring balance
- Stopwatch
- Displacement and time intervals
- Position and velocity
- Force
- Time interval
26.Arrange the following steps in the correct order for an experiment to determine the relationship between mass and acceleration for a constant net force.
Medium- Record the acceleration for each mass
- Add masses to the cart and repeat
- Set up a friction-compensated track with a constant hanging mass
- Measure the acceleration of the cart with no extra mass
- Plot a graph of acceleration against the inverse of total mass
27.In an experiment to measure the acceleration due to gravity using a falling ball and a light gate, a student drops a ball from a known height and measures the time to fall. The calculated value of g is consistently lower than 9.8 m/s². Which of the following could explain this discrepancy?
Medium- AThe ball was dropped from a height slightly less than measured
- BThe ball was not perfectly spherical
- CAir resistance was ignored
- DThe light gate was triggered by the ball's shadow
28.Which of the following is a contact force?
Easy- AGravitational force
- BFrictional force
- CMagnetic force
- DElectrostatic force
29.Which of the following are examples of simple machines? (Select all that apply)
Easy- ALever
- BPulley
- CBattery
- DInclined plane
- ESpring balance
30.A force is a vector quantity because it has both magnitude and direction.
EasyTrue or false?
31.Match each type of force to its description.
Medium- Gravitational force
- Frictional force
- Normal force
- Elastic force
- Force that opposes motion between surfaces
- Force exerted by a stretched spring
- Force that pulls objects toward Earth
- Force perpendicular to a surface supporting an object
32.Arrange the following steps in the correct order to draw a force arrow diagram for a book resting on a table.
Medium- Identify all objects interacting with the book
- Draw a dot to represent the book
- Draw and label arrows for each force acting on the book, with length proportional to magnitude
- Indicate the direction of each force with an arrowhead
33.A 0.5 kg ball is thrown upward. At the top of its path, what is the net force acting on the ball? (Ignore air resistance)
Medium- A0 N
- B4.9 N downward
- C9.8 N downward
- D0.5 N downward
34.Which of the following statements about balanced forces are correct? (Select all that apply)
Medium- AThe net force is zero
- BThe object must be stationary
- CThe object can be moving at constant velocity
- DThe object is accelerating
35.A car is moving at a constant speed of 20 m/s on a straight, level road. Which of the following statements about the forces acting on the car is correct?
Medium- AThe net force is zero because the car is moving at constant velocity.
- BThe net force is in the direction of motion because the car is moving.
- CThe net force is equal to the driving force because friction is negligible.
- DThe net force is equal to the weight of the car because it is on a level road.
36.Friction is a force that always opposes motion.
EasyTrue or false?
37.A 5 kg box is pulled across a rough floor with a horizontal force of 30 N. The frictional force is 10 N. What is the acceleration of the box?
Medium- A4 m/s²
- B6 m/s²
- C8 m/s²
- D2 m/s²
38.In an experiment to investigate the effect of net force on acceleration, a student pulls a trolley along a friction-compensated runway with an elastic cord. The student varies the force by stretching the cord by different amounts. Which of the following must be kept constant to ensure a fair test?
Medium- AThe mass of the trolley
- BThe length of the runway
- CThe type of elastic cord
- DThe distance the trolley travels
39.In an experiment to measure friction between a wooden block and a table, a student pulls the block with a spring balance at constant speed. Which of the following statements are correct? (Select all that apply)
Medium- AThe reading on the spring balance equals the frictional force.
- BThe block is in equilibrium because it moves at constant speed.
- CThe net force on the block is zero.
- DThe pulling force must be greater than friction to keep the block moving.
40.Force is a scalar quantity because it only has magnitude.
EasyTrue or false?
41.Complete the sentence:
EasyThe force that opposes motion between two surfaces in contact is called ____.
42.A 5 kg object is accelerating at 2 m/s². What is the net force acting on it? (in newtons)
Easy43.What is the name of the force that acts on an object moving through air and opposes its motion?
Easy44.A 10 kg object is accelerating at 3 m/s². What is the net force acting on it? (in newtons)
Easy45.What is the name of the force that opposes motion between two surfaces in contact?
Easy46.A car of mass 1200 kg accelerates uniformly from rest to 20 m/s in 10 seconds. What is the net force acting on the car? (in newtons)
Medium47.What is the name of the force that pulls objects towards the centre of the Earth?
Easy48.A force of 20 N is applied to push a box across a floor. The frictional force opposing the motion is 8 N. What is the net force acting on the box? (in newtons)
Easy49.Complete the sentence using the words 'push' or 'pull'.
EasyA force is a ____ or a ____.
50.What is the SI unit of force?
Easy51.A 5 kg object is accelerating at 4 m/s². What is the net force acting on it? (in newtons)
Easy52.Fill in the blanks with the correct terms.
EasyAccording to Newton's first law, an object at rest will remain at ____, and an object in motion will continue in motion with constant ____ and direction, unless acted upon by an unbalanced ____.
53.Explain why a rocket can accelerate in space where there is no air.
Medium54.Explain why a book resting on a table is not moving, even though the force of gravity is pulling it downward.
Medium55.Describe how you would design an experiment to test Newton's second law by varying both the net force and the mass. What measurements would you take and how would you analyse the data?
Hard56.In an experiment to measure the acceleration due to gravity using a falling ball and a light gate, a student drops a ball from a known height and measures the time it takes to fall. Explain why it is important to release the ball from rest and to measure the height accurately.
Medium57.A 5 kg object is accelerating at 2 m/s². What is the net force acting on it? (in newtons)
Easy- A10 N
- B11 N
- C9 N
- D12 N
58.A 10 kg object is accelerating at 3 m/s². What is the net force acting on it? (in newtons)
Easy- A36 N
- B30 N
- C33 N
- D27 N
59.A car of mass 1200 kg accelerates uniformly from rest to 20 m/s in 10 seconds. What is the net force acting on the car? (in newtons)
Medium- A2160 N
- B2880 N
- C2640 N
- D2400 N
60.A force of 20 N is applied to push a box across a floor. The frictional force opposing the motion is 8 N. What is the net force acting on the box? (in newtons)
Easy- A11 N
- B13 N
- C14 N
- D12 N
61.A 5 kg object is accelerating at 4 m/s². What is the net force acting on it? (in newtons)
Easy- A24 N
- B20 N
- C18 N
- D22 N
字卡
What is a force in physics?
A force is an action that can change an object's velocity or shape, resist other forces, or cause pressure changes in a fluid. It is a vector quantity with both magnitude and direction.
What is the SI unit of force?
The SI unit of force is the newton (N).
What symbol is commonly used to represent force?
Force is often represented by the symbol F.
Is force a scalar or vector quantity?
Force is a vector quantity because both its magnitude and direction are important.
What is the net force on an object?
The net force is the vector sum of all forces acting on an object.
What does it mean if the net force on an object is zero?
If the net force is zero, the object is in equilibrium; it remains at rest or moves with constant velocity.
What are balanced forces?
Balanced forces are forces that are equal in size and opposite in direction, resulting in a net force of zero and no change in motion.
What are unbalanced forces?
Unbalanced forces are forces that are not equal and opposite, resulting in a net force that causes a change in motion (acceleration).
What is gravity?
Gravity is a force of attraction between objects with mass. On Earth, it pulls objects toward the centre of the planet.
How does mass affect the force of gravity?
The force of gravity between two objects increases with the mass of each object. Larger masses experience a greater gravitational force.
What is a force arrow diagram?
A force arrow diagram uses arrows to represent forces acting on an object. The arrow's length shows the magnitude, and the direction shows the force's direction.
What is a simple machine?
A simple machine is a device that changes the magnitude or direction of a force, making work easier. Examples include levers and pulleys.
How does a lever make work easier?
A lever multiplies the input force by using a rigid bar that pivots on a fulcrum, allowing a smaller force to lift a heavier load over a greater distance.
What is a pulley?
A pulley is a wheel with a groove that holds a rope or cable. It changes the direction of a force and can provide mechanical advantage when multiple pulleys are used.
What is mechanical advantage?
Mechanical advantage is the factor by which a machine multiplies the input force. It is the ratio of output force to input force.
What is friction?
Friction is a force that opposes motion between two surfaces in contact. It acts parallel to the surfaces and opposite to the direction of motion.
What is a normal force?
The normal force is the support force exerted by a surface on an object in contact with it. It acts perpendicular to the surface.
What is an elastic force?
An elastic force is a force that restores a deformed object (like a spring) to its original shape. It is proportional to the displacement (Hooke's law).
What is torque?
Torque is the rotational version of force. It causes changes in the rotational speed of an object and depends on the force applied and the distance from the pivot point.
What did Galileo contribute to the understanding of force?
Galileo showed that objects accelerate due to gravity independent of their mass and that force is needed to change motion, not to sustain it.
What is Newton's first law of motion?
Newton's first law states that an object at rest stays at rest and an object in motion stays in motion with constant velocity unless acted on by a net external force.
What is Newton's second law of motion?
Newton's second law states that the net force on an object equals the product of its mass and acceleration (F = ma).
What is Newton's third law of motion?
Newton's third law states that for every action force, there is an equal and opposite reaction force.
What are the four fundamental interactions in modern physics?
The four fundamental interactions are strong, electromagnetic, weak, and gravitational, listed in decreasing order of strength.