Unlock hundreds more features
Save your Quiz to the Dashboard
View and Export Results
Use AI to Create Quizzes and Analyse Results

OR
Sign inSign in with Facebook
Sign inSign in with Google
Quizzes > High School Quizzes > Science

Physics Torque Practice Quiz

Sharpen your torque skills with practice questions

Difficulty: Moderate
Grade: Grade 11
Study OutcomesCheat Sheet
Colorful paper art promoting a Torque mastery quiz for high school physics students.

What does torque measure in rotational dynamics?
The linear acceleration of an object
The frictional resistance to motion
The gravitational force acting on an object
The tendency of a force to rotate an object about an axis
Torque quantifies the tendency of a force to produce rotation about an axis. It is a fundamental concept in rotational dynamics linking force and rotational effect.
Which equation correctly represents the torque (τ) produced by a force (F) applied at a distance (r) and angle (θ) from the lever arm?
τ = rF sinθ
τ = F sinθ
τ = rF cosθ
τ = r + F + sinθ
The correct formula for torque is τ = rF sinθ, where r is the distance from the pivot and θ is the angle between the force and the lever arm. This formula indicates that only the perpendicular component of the force contributes to rotation.
What are the SI units for torque?
Meters per second (m/s)
Kilograms (kg)
Newton-meters (N·m)
Joules (J)
Torque is measured in Newton-meters (N·m), which reflects the product of force and distance. Although joules have the same dimensional units, torque is not a measure of energy.
What is the lever arm in the context of torque calculation?
The distance between the force and the object's center of mass
The angle at which the force is applied
The perpendicular distance from the axis of rotation to the line of action of the force
The entire length of the rotating object
The lever arm is defined as the shortest (perpendicular) distance from the pivot point to the line along which the force acts. This distance directly influences how effective a force is at generating torque.
If a force is applied perpendicular to the lever arm, what is the value of sinθ in the torque equation?
0.5
0
1
Depends on the magnitude of the force
When a force is applied perpendicular to the lever arm, the angle θ is 90° and sin90° equals 1. This scenario maximizes the torque produced for a given force and lever arm length.
A 60 N force is applied at the end of a 0.25 m long wrench at an angle of 60° to the lever arm. What is the magnitude of the torque?
10 N·m
15 N·m
26 N·m
30 N·m
Torque is calculated as τ = rF sinθ. Substituting the given values: 0.25 m à - 60 N à - sin60° (approximately 0.866) yields roughly 26 N·m.
In rotational equilibrium, what must be true about the net torque acting on the system?
The net torque is irrelevant in rotational equilibrium.
The net torque must be at its maximum value.
The net torque must be zero.
The net torque must be equal to the weight of the system.
For an object to be in rotational equilibrium, the sum of all torques must cancel out to zero. This prevents any angular acceleration from occurring.
When two forces create a couple, what is the net force and net torque?
Both net force and net torque are nonzero.
Net force is nonzero, but net torque is zero.
Both net force and net torque are zero.
Net force is zero, but net torque is nonzero.
A couple consists of two equal and opposite forces whose lines of action are offset, resulting in no net force but a nonzero net torque. This produces a pure rotational effect without linear acceleration.
Which factor does NOT directly affect the magnitude of torque?
Lever arm length
Magnitude of the force
Mass of the object
Angle between force and lever arm
Torque is determined by the force magnitude, the length of the lever arm, and the sine of the angle between them. The mass of the object does not directly enter into the torque calculation.
Why is the angle between the force and the lever arm crucial in determining the effective torque?
Because it alters the object's mass.
Because it influences the component of the force that produces rotation.
Because it changes the distance from the pivot.
Because it determines the gravitational force on the object.
Only the component of the force that acts perpendicular to the lever arm contributes to torque. This is mathematically represented by the sine of the angle in the torque equation.
A seesaw is balanced when the torques produced by the weights are equal. Which of the following best describes the condition for balance?
Weight1 / Distance1 = Weight2 / Distance2
Weight1 x Distance1 = Weight2 x Distance2
Weight1 + Distance1 = Weight2 + Distance2
Weight1 - Distance1 = Weight2 - Distance2
A balanced seesaw requires that the torques on either side of the pivot be equal. This condition is met when the product of weight and its distance from the pivot is the same on both sides.
In the torque equation τ = rF sinθ, what happens to the torque if the force is applied at an angle less than 90°?
The torque increases because sinθ becomes larger.
The torque decreases because sinθ is less than 1.
The force effectively becomes zero.
The torque remains unchanged.
When the applied force makes an angle less than 90° with the lever arm, the sine of the angle is less than 1, thus decreasing the effective torque. This highlights the importance of applying force as perpendicularly as possible.
Consider a door rotating about its hinges. If the force is applied closer to the hinges, how is the resulting torque affected?
The torque becomes zero at any point on the door.
The torque remains the same regardless of the force application point.
The torque increases because the force is applied more directly.
The torque decreases because the lever arm is shorter.
Torque is directly proportional to the distance from the pivot point. A force applied closer to the hinges has a shorter lever arm and thus produces less torque.
In rotational dynamics, which quantity plays a role analogous to mass in linear motion?
Angular momentum
Torque
Moment of inertia
Angular velocity
The moment of inertia quantifies an object's resistance to angular acceleration, much like mass quantifies resistance to linear acceleration in translational motion. It depends on how mass is distributed relative to the axis of rotation.
How does increasing the distance from the pivot affect the torque generated by a force of constant magnitude and direction?
It squares the torque.
It leaves the torque unchanged.
It increases the torque linearly with distance.
It decreases the torque.
Since torque is directly proportional to the lever arm distance (τ = rF sinθ), increasing the distance results in a linear increase of the torque produced. This demonstrates the importance of the lever arm position.
A uniform beam is balanced about its midpoint. A 200 N force is applied 3 m from the pivot on one side. At what distance must a 150 N force be applied on the opposite side to balance the beam?
2 m
5 m
4 m
3 m
The torque generated by the 200 N force is 200 N à - 3 m = 600 N·m. To balance this torque, the 150 N force must be applied at a distance of 600 N·m / 150 N = 4 m from the pivot.
Torque is defined as the cross product of the position vector and the force vector. Which statement best describes the direction of the resulting torque vector?
It is perpendicular to both the force and the position vector.
It is parallel to the position vector.
It lies in the same plane as the force and position vectors.
It opposes the direction of the applied force.
Since torque is given by Ï„ = r x F, the resulting vector is perpendicular to the plane formed by the position and force vectors. This is a fundamental property of the cross product in vector mathematics.
A 50 N force is applied at 1.2 m from a hinge at a 30° angle relative to the door. What is the effective torque, and what would be the maximum torque if the force were applied perpendicularly?
Effective torque is 30 N·m, and maximum torque is 30 N·m
Effective torque is 30 N·m, and maximum torque is 60 N·m
Effective torque is 25 N·m, and maximum torque is 75 N·m
Effective torque is 60 N·m, and maximum torque is 120 N·m
The effective torque is calculated by τ = 1.2 m à - 50 N à - sin30° which equals 30 N·m. If the force were applied perpendicularly (sin90° = 1), the maximum torque would be 1.2 m à - 50 N = 60 N·m.
Two opposing torques act on a rotating body: one of 45 N·m clockwise and another of 30 N·m counterclockwise. What is the net torque and its direction?
75 N·m clockwise
15 N·m clockwise
75 N·m counterclockwise
15 N·m counterclockwise
Since torques in opposite directions subtract from one another, the net torque is 45 N·m - 30 N·m = 15 N·m clockwise. The direction is determined by the larger contributing torque.
For a rotating disc, if a net torque of 20 N·m is applied to a disc with a moment of inertia of 4 kg·m², what is the resulting angular acceleration?
5 rad/s²
0.2 rad/s²
80 rad/s²
4 rad/s²
Using the rotational analog of Newton's second law (τ = Iα), the angular acceleration is found by α = 20 N·m / 4 kg·m² = 5 rad/s². This demonstrates how net torque and moment of inertia determine angular acceleration.
0
{"name":"What does torque measure in rotational dynamics?", "url":"https://www.quiz-maker.com/QPREVIEW","txt":"What does torque measure in rotational dynamics?, Which equation correctly represents the torque (τ) produced by a force (F) applied at a distance (r) and angle (θ) from the lever arm?, What are the SI units for torque?","img":"https://www.quiz-maker.com/3012/images/ogquiz.png"}

Study Outcomes

  1. Understand the definition and units of torque.
  2. Apply formulas to calculate torque in various physical scenarios.
  3. Analyze the effects of lever arm length and force direction on rotational motion.
  4. Synthesize problem-solving strategies for rotational dynamics challenges.
  5. Evaluate the relationship between force, distance, and rotational equilibrium.

Physics Torque Cheat Sheet

  1. Understanding Torque - Torque is the rotational equivalent of force that makes objects twist or spin around an axis, like opening a stubborn jar or turning a steering wheel. Think of it as the "twist power" you apply, combining the strength of your push with the distance from the pivot point. Once you've got this down, you'll never look at a wrench - or a playground seesaw - the same way again! Britannica: Torque
  2. Torque Formula - The magic equation τ = r × F × sin(θ) ties together the lever arm (r), the force you apply (F), and the angle (θ) between them to compute torque. It's like mixing ingredients in just the right proportions: tilt the force angle and you change the twist output! Experiment with different angles and distances in practice problems to see how each factor plays its part. OpenStax: Torque Formula
  3. Right-Hand Rule - To figure out which way torque points, use your right hand: aim your fingers along the lever arm (r), curl them toward the force (F), and your thumb shows the direction of Ï„. It's like giving your thumb a job title - "Chief Torque Director" - every time you solve a rotational problem. Practice this gesture to build intuitive muscle memory for torque directions! U of Guelph Tutorial: Right-Hand Rule
  4. SI Units of Torque - In the metric world, torque is measured in Newton-meters (N·m), which literally means "newtons of force pushing at a meter of distance." Remember, it's not energy (joules), so don't mix them up - torque is all about turning, not doing work over a displacement. Keep your units tidy and your answers will shine in lab reports! Britannica: SI Units
  5. Lever Arm Concept - The lever arm (or moment arm) is the perpendicular distance from the pivot to your line of action, and it's key to maximizing torque. A longer lever arm gives you more twist for the same push - hello, long-handled wrenches! Visualizing this distance helps you optimize real-world tools and ace those torque calculation questions. PhysicsTeacher.in: Lever Arm
  6. Static vs. Dynamic Torque - Static torque holds objects stationary - like propping a door open - while dynamic torque produces angular acceleration, spinning things faster or slower. Static torque balances forces without motion, whereas dynamic torque gets the merry-go-round turning. Knowing the difference is crucial for solving equilibrium versus motion problems! GeeksforGeeks: Static vs. Dynamic
  7. Torque in Equilibrium - When an object is in rotational equilibrium, the sum of all torques acting on it is zero, so there's no net twist causing rotation. It's like balancing on a seesaw with equal weights on each side - you stay level and motionless. Apply this rule to analyze balanced beams, ladders, and even tightrope walkers! U of Guelph: Rotational Equilibrium
  8. Calculating Net Torque - With multiple forces at play, calculate each individual torque (remembering its direction) and algebraically sum them for the net effect. Positive torques spin one way, negatives the other - think of them as opposing teams in a tug-of-war. This skill is a must for complex systems like multi-force levers and machinery analysis. OpenStax: Net Torque
  9. Torque and Angular Acceleration - Newton's second law for rotation states τ = I × α, meaning torque equals moment of inertia (I) times angular acceleration (α). Increase the torque and you speed up the spin; increase inertia and you resist changes in rotation. Mastering this relation unlocks the physics behind merry-go-rounds, flywheels, and engine crankshafts! OpenStax: τ = Iα
  10. Real-World Applications - From opening faucets to tightening bolts and propelling rockets, torque is the unsung hero of rotational mechanics in everyday life and cutting-edge tech. Engineers harness torque to design gears, turbines, and steering systems, while chefs use it unconsciously when twisting jar lids. Spotting torque in action makes studying physics feel as natural as turning a doorknob! BYJU'S: Torque in Real Life
Make a Quiz (FREE) Copy & Edit This Quiz Create a Quiz with AI

Science Quizzes

Powered by: Quiz Maker