Motion and Newton's laws
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1.Newton's first law of motion states that an object at rest will stay at rest, and an object in motion will stay in motion with a constant speed and direction, unless acted upon by a(n):
Easy- Aunbalanced force
- Bbalanced force
- Cinertia
- Dmomentum
2.The tendency of an object to resist changes in its state of motion is called:
Easy- Aweight
- Binertia
- Cacceleration
- Dforce
3.According to Newton's third law, when you push against a wall, the wall pushes back on you with an equal and opposite force.
EasyTrue or false?
4.A 2 kg object accelerates at 3 m/s². What is the net force acting on it?
Easy- A6 N
- B1.5 N
- C5 N
- D0.67 N
5.Match each law of motion with its correct description.
Easy- First law
- Second law
- Third law
- F = ma
- Action and reaction forces are equal and opposite
- An object maintains its state of motion unless acted on by a net force
6.Arrange the following steps in the correct order to calculate acceleration from a force and mass using Newton's second law.
Medium- Identify the net force acting on the object
- Write the formula F = ma
- Divide the net force by the mass
- Check units: newtons divided by kilograms gives m/s²
7.Which of the following statements about Newton's laws are correct? (Select all that apply.)
Medium- ANewton's first law is also called the law of inertia.
- BAccording to Newton's second law, acceleration is directly proportional to mass.
- CNewton's third law implies that forces always occur in pairs.
- DAn object moving at constant velocity has zero net force acting on it.
- EThe unit of force, the newton, is equivalent to kg·m/s².
8.If the net force on an object is zero, the object must be at rest.
EasyTrue or false?
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9.Match each Newton's law with its correct description.
Easy- First law
- Second law
- Third law
- F = ma
- For every action there is an equal and opposite reaction
- An object at rest stays at rest unless acted upon by a force
10.Arrange the following steps in the correct order to calculate the net force on an object given its mass and acceleration.
Easy- Identify the mass of the object
- Identify the acceleration of the object
- Multiply mass by acceleration
- Write the result with the unit newtons
11.Which of the following statements about Newton's third law are correct? (Select all that apply.)
Medium- AAction and reaction forces act on the same object
- BAction and reaction forces have equal magnitudes
- CAction and reaction forces act in opposite directions
- DAction and reaction forces cancel each other out
- EAction and reaction forces always occur in pairs
12.According to Newton's first law, an object moving at constant velocity requires a net force to keep it moving.
EasyTrue or false?
13.Which of the following best describes the concept of inertia?
Easy- AThe tendency of an object to resist changes in its state of motion
- BThe force that keeps an object moving
- CThe acceleration of an object due to gravity
- DThe product of mass and velocity
14.A 1000 kg car accelerates from rest to 20 m/s in 5 s. What is the net force acting on the car?
Medium- A4000 N
- B2000 N
- C10000 N
- D5000 N
15.Which of the following are true about Newton's second law? (Select all that apply.)
Medium- AIt relates net force, mass, and acceleration
- BIt can be written as F = ma
- CIt applies only to objects at rest
- DAcceleration is inversely proportional to mass when force is constant
- EForce is directly proportional to acceleration when mass is constant
16.A car of mass 1200 kg accelerates from 10 m/s to 25 m/s in 6 seconds. What is the net force acting on the car? (Assume constant acceleration.)
Medium- A3000 N
- B2500 N
- C2000 N
- D1800 N
17.A 0.5 kg ball is thrown vertically upward with an initial speed of 20 m/s. Ignoring air resistance, what is the net force acting on the ball at the highest point of its trajectory?
Hard- A0 N
- B4.9 N downward
- C9.8 N downward
- D19.6 N downward
- 18.Hard
The graph shows the velocity of an object over time. The object starts from rest and moves in a straight line. The velocity increases linearly from 0 to 20 m/s in 4 seconds, then remains constant at 20 m/s for 2 seconds, then decreases linearly to 0 in 4 seconds. What is the net force on the object during the first 4 seconds if its mass is 5 kg?
Time (s) Velocity (m/s) 0 0 1 5 2 10 3 15 4 20 5 20 6 20 7 15 8 10 9 5 10 0 - A25 N
- B20 N
- C10 N
- D5 N
19.A 10 kg box is pushed with a force of 50 N across a rough floor, resulting in an acceleration of 3 m/s². Which of the following are true? (Select all that apply.)
Hard- AThe net force on the box is 30 N.
- BThe frictional force is 20 N.
- CThe net force is 50 N.
- DThe frictional force is 30 N.
- EThe box's acceleration is constant if forces are constant.
20.In an experiment to verify Newton's second law, a student measures the acceleration of a trolley pulled by a hanging mass over a friction-compensated ramp. The student varies the hanging mass and records the acceleration. Which of the following graphs best represents the expected relationship between acceleration (a) and the hanging mass (m)?
Medium- Aa is directly proportional to m
- Ba is inversely proportional to m
- Ca is proportional to the square of m
- Da is independent of m
21.A student investigates the motion of a cart on a horizontal track. The cart is attached to a force sensor and pulled with a constant force. The student records the velocity at regular intervals. Which of the following experimental procedures is most important to ensure that the net force on the cart is constant?
Medium- AUse a smooth track and lubricate the wheels
- BKeep the pulling force constant and compensate for friction by tilting the track slightly
- CMeasure the mass of the cart before each run
- DUse a motion sensor instead of a ticker timer
22.In an experiment to investigate Newton's second law, it is acceptable to use a ticker timer and tape to measure acceleration if the tape is pulled through the timer by the moving object.
EasyTrue or false?
23.A student sets up an experiment to investigate the relationship between force and acceleration. Which of the following are necessary steps to ensure valid results? (Select all that apply.)
Medium- AMeasure the mass of the object accurately
- BUse a constant force throughout the experiment
- CRecord the time taken for the object to travel a fixed distance
- DRepeat the experiment multiple times and calculate an average
24.Match each experimental method with its purpose in investigating motion and forces.
Medium- Ticker timer and tape
- Light gates and data logger
- Motion sensor
- Force sensor
- Measures velocity at specific points
- Records position over time continuously
- Measures force directly
- Provides a record of position at regular intervals
25.Arrange the following steps in the correct order for an experiment to verify Newton's second law using a trolley and hanging mass.
Medium- Measure the acceleration of the trolley using a ticker timer or motion sensor
- Set up a friction-compensated ramp
- Record the mass of the trolley and the hanging mass
- Release the trolley and allow it to accelerate
- Vary the hanging mass and repeat the experiment
26.Which of the following is the correct statement of Newton's first law of motion?
Easy- AAn object at rest stays at rest and an object in motion stays in motion with constant velocity unless acted upon by a net external force.
- BThe acceleration of an object is directly proportional to the net force and inversely proportional to its mass.
- CFor every action, there is an equal and opposite reaction.
- DForce equals mass times acceleration.
27.Newton's third law states that if object A exerts a force on object B, then object B exerts a force on object A that is equal in magnitude and opposite in direction.
EasyTrue or false?
28.An object with zero net force acting on it must be at rest.
EasyTrue or false?
29.Which property of an object is a measure of its inertia?
Easy- AMass
- BWeight
- CVolume
- DDensity
30.Which of the following statements about Newton's first law are correct? (Select all that apply.)
Medium- AIt is also known as the law of inertia.
- BIt states that a net force is required to keep an object moving at constant velocity.
- CIt applies only to objects at rest.
- DIt describes the behaviour of objects when no net force acts on them.
31.Arrange the following steps in the correct order to calculate the net force on an object using Newton's second law.
Easy- Identify the mass of the object.
- Determine the acceleration of the object.
- Multiply the mass by the acceleration to find the net force.
32.According to Newton's third law, when you push on a wall, the wall pushes back on you with an equal force in the same direction.
EasyTrue or false?
33.Arrange the following steps in the correct order to calculate the acceleration of an object given the net force and mass using Newton's second law.
Medium- Write down Newton's second law: F = ma
- Identify the net force acting on the object
- Identify the mass of the object
- Rearrange the formula to solve for acceleration: a = F/m
- Substitute the values and calculate
34.A car of mass 1200 kg accelerates uniformly from rest to 20 m/s in 8 seconds. What is the net force acting on the car?
Medium- A1500 N
- B3000 N
- C24000 N
- D9600 N
35.A 2 kg object is moving at 3 m/s on a frictionless surface. Which of the following statements are correct? (Select all that apply.)
Medium- AThe net force on the object is 6 N.
- BThe net force on the object is 0 N.
- CThe object will continue moving at 3 m/s unless acted upon by a force.
- DThe object's momentum is 6 kg·m/s.
- EThe object is accelerating.
36.According to Newton's second law, the acceleration of an object is directly proportional to its mass.
EasyTrue or false?
37.Match each quantity with its correct SI unit.
Easy- Force
- Mass
- Acceleration
- m/s²
- kg
- N
38.In an experiment to verify Newton's second law, a student uses a trolley on a friction-compensated ramp. The trolley is pulled by a hanging mass attached via a string over a pulley. The student measures the acceleration of the trolley for different hanging masses. Which of the following is the most important reason for using a friction-compensated ramp?
Medium- ATo ensure the net force on the trolley is exactly equal to the weight of the hanging mass
- BTo eliminate the need to measure the mass of the trolley
- CTo make the acceleration of the trolley independent of its mass
- DTo reduce the acceleration so it is easier to measure
39.A student sets up an experiment to investigate the relationship between force and acceleration using a trolley, ticker timer, and hanging masses. Which of the following are necessary steps to ensure valid results? (Select all that apply.)
Hard- AUsing a friction-compensated ramp to eliminate the effect of friction
- BMeasuring the acceleration by analysing the ticker tape with a ruler and stopwatch
- CVarying the hanging mass while keeping the trolley mass constant
- DRepeating the experiment for each hanging mass at least three times
- EPlotting a graph of force vs acceleration and checking for a straight line through the origin
40.In an experiment to investigate Newton's second law, it is acceptable to use a ticker timer and tape to measure acceleration if the tape is pulled through the timer by the moving trolley.
EasyTrue or false?
41.Complete the sentence.
EasyNewton's second law can be written as the formula: force = ____ × ____.
42.A car of mass 1500 kg accelerates from rest to 20 m/s in 10 seconds. What is the net force acting on the car? (Assume constant acceleration.)
Medium43.What is the SI unit of force?
Easy44.A 5 kg object experiences a net force of 20 N. What is its acceleration in m/s²?
Medium45.Complete the sentence using the correct terms.
EasyNewton's second law states that the acceleration of an object is directly proportional to the ____ acting on it and inversely proportional to its ____.
46.A 2 kg object experiences a net force of 8 N. What is its acceleration in m/s²?
Medium47.A 0.2 kg ball is dropped from a height. Ignoring air resistance, what is the net force on the ball after 1 second of free fall? (Take g = 9.8 m/s²)
Medium48.A car accelerates uniformly from rest to 25 m/s in 10 seconds. What is its acceleration in m/s²?
Medium49.Complete the sentence using the correct word.
EasyNewton's first law is often called the law of ____.
50.Fill in the blanks to complete the statement of Newton's second law.
EasyThe net force acting on an object is equal to the product of its ____ and its ____.
51.A 1500 kg car is moving at 20 m/s. The driver applies the brakes and the car comes to a stop in 5 seconds. What is the magnitude of the average braking force in newtons?
Medium52.A 0.5 kg ball is thrown vertically upward with an initial speed of 15 m/s. Ignoring air resistance, what is the net force acting on the ball at its highest point? (Take g = 9.8 m/s²)
Medium53.Explain why a person in a car who is not wearing a seatbelt continues to move forward when the car suddenly stops, in terms of Newton's laws.
Medium54.Explain why a passenger in a car that suddenly stops tends to lurch forward, using Newton's first law.
Medium55.Describe a method to measure the acceleration of a falling object using a ticker timer. Include how you would calculate the acceleration from the tape, and explain one source of error in this experiment.
Hard56.Explain how you would design an experiment to test Newton's third law using two force sensors. What would you expect to observe?
Medium57.Describe an experiment to verify Newton's second law using a trolley and a hanging mass. Include how you would measure acceleration and what you would vary.
Hard58.A car of mass 1500 kg accelerates from rest to 20 m/s in 10 seconds. What is the net force acting on the car? (Assume constant acceleration.)
Medium- A3600 N
- B2700 N
- C3300 N
- D3000 N
59.A 5 kg object experiences a net force of 20 N. What is its acceleration in m/s²?
Easy- A3 m/s²
- B5 m/s²
- C4 m/s²
- D6 m/s²
60.A 2 kg object experiences a net force of 8 N. What is its acceleration in m/s²?
Easy- A3 m/s²
- B6 m/s²
- C5 m/s²
- D4 m/s²
61.A 0.2 kg ball is dropped from a height. Ignoring air resistance, what is the net force on the ball after 1 second of free fall? (Take g = 9.8 m/s²)
Medium- A3.96 N
- B1.96 N
- C0.96 N
- D2.96 N
62.A car accelerates uniformly from rest to 25 m/s in 10 seconds. What is its acceleration in m/s²?
Easy- A2.5 m/s²
- B4.5 m/s²
- C3.5 m/s²
- D1.5 m/s²
63.A 1500 kg car is moving at 20 m/s. The driver applies the brakes and the car comes to a stop in 5 seconds. What is the magnitude of the average braking force in newtons?
Medium- A6000 N
- B6600 N
- C5400 N
- D7200 N
64.A 0.5 kg ball is thrown vertically upward with an initial speed of 15 m/s. Ignoring air resistance, what is the net force acting on the ball at its highest point? (Take g = 9.8 m/s²)
Medium- A3.9 N
- B6.9 N
- C4.9 N
- D5.9 N
闪卡
What is Newton's first law of motion?
A body remains at rest, or in motion at a constant speed in a straight line, unless acted upon by a net force.
What is Newton's second law of motion?
The net force on a body equals its mass times its acceleration (F = ma), or equivalently, the rate of change of momentum.
What is Newton's third law of motion?
If two bodies exert forces on each other, these forces have the same magnitude but opposite directions.
What is the formula for average velocity?
Average velocity = Δs/Δt = (s(t1) - s(t0))/(t1 - t0), where s is position and t is time.
What does a positive average velocity indicate?
A positive average velocity means the position coordinate increases over the time interval.
What does a negative average velocity indicate?
A negative average velocity indicates a net decrease in position over the time interval.
What does an average velocity of zero mean?
It means the body ends the time interval at the same position as it began.
How is instantaneous velocity defined?
Instantaneous velocity is the derivative of position with respect to time: v = ds/dt.
What is the relationship between force, mass, and acceleration?
The net force on an object equals its mass multiplied by its acceleration (F = ma).
What is the SI unit of force?
The newton (N). One newton is the force needed to accelerate a 1 kg mass at 1 m/s².
What is inertia?
Inertia is the tendency of an object to resist changes in its state of motion, as described by Newton's first law.
What is the difference between mass and weight?
Mass is the amount of matter in an object (kg), while weight is the force of gravity on that mass (W = mg).
What is the formula for acceleration?
Acceleration = change in velocity / time taken, or a = (v - u)/t, where v is final velocity, u is initial velocity.
What does a distance-time graph show?
It shows how distance changes over time. The slope of the line gives the speed.
What does a velocity-time graph show?
It shows how velocity changes over time. The slope gives acceleration, and the area under the graph gives displacement.
What is the equation for speed?
Speed = distance / time (v = d/t) for constant speed.
What is the difference between speed and velocity?
Speed is a scalar (magnitude only), while velocity is a vector (magnitude and direction).
What is momentum?
Momentum is the product of an object's mass and velocity: p = mv. It is a vector quantity.
How is Newton's second law expressed in terms of momentum?
The net force equals the rate of change of momentum: F = Δp/Δt.
What is the principle of conservation of momentum?
In a closed system, the total momentum before an interaction equals the total momentum after, provided no external forces act.
What is an example of Newton's third law?
When you push a wall, the wall pushes back on you with an equal and opposite force.
What is the difference between balanced and unbalanced forces?
Balanced forces produce no net force, so no acceleration; unbalanced forces produce a net force and cause acceleration.
What is the effect of friction on motion?
Friction is a force that opposes motion, often causing deceleration or preventing motion from starting.
What is the relationship between force and acceleration?
Acceleration is directly proportional to the net force and inversely proportional to the mass (a = F/m).
What is the difference between average and instantaneous velocity?
Average velocity is over a time interval; instantaneous velocity is at a single moment, found using calculus.