PencilGo

Grade 11 · Science · Physics

11th grade Balanced forces, equilibrium and inertia worksheet

6 printable versionsBuilding Confidence10 questions · answer keyFree · no account

Level: Building Confidence · On Level · Challenge Me

When it’s done, scan the sheet with your phone and PencilGo marks it and picks the next one. Create a free account

Version
Print

Balanced forces, equilibrium and inertia

Grade 11 Science Worksheet - Building Confidence

NameDate

Circle the best answer, or write your answer on the line.

  1. A 4 kg box sits at rest on a table while Ari presses straight down on it with 15 N. What is the table's normal force on the box?

  2. A 2.5 kg box sits at rest on a table while Bo presses straight down on it with 6 N. What is the table's normal force on the box?

  3. A 6 kg box sits at rest on a table while Esme presses straight down on it with 20 N. What is the table's normal force on the box?

  4. Read this first

    Free-body diagram (example data)

    a crate on the floor of mass 5 kg, with arrows from its center: weight 49 N down; normal force 49 N up; push 20 N right; friction 12 N left.

  5. Using the free-body diagram, is the crate in equilibrium, Jun?

    • Yes: friction balances the push, so nothing is left
    • No: the net force is 32 N to the right, from 20 + 12
    • Yes: the weight and the normal force cancel each other
    • No: the net force is 8 N to the right

  6. The cart rolls right at a steady speed. Using the diagram, is it in equilibrium, Kira?

    • No: it is moving, so some net force must act to the right
    • No: the push and friction add up to 30 N of net force
    • Yes: every pair cancels, so its velocity stays the same
    • Yes, but only if the cart were at rest and not moving

  7. Using the diagram, what is true of the lamp, Luz?

    • It is in equilibrium, since the cable holds the lamp up
    • The net force is 5.6 N downward, so the lamp is falling
    • The net force is 5.6 N upward, so it is not in equilibrium
    • The net force is 35 N upward, the cable's whole pull

  8. A 1,000 kg car and a 2,000 kg truck both go 20 m/s and brake with the same 8,000 N force. Which statement is true, Noah?

    • Both stop in 25 m, since they started at the same speed of 20 m/s
    • The truck has more inertia but stops in half the distance
    • The truck has more inertia and needs twice the distance to stop
    • The car has more inertia and needs twice the distance to stop

  9. A probe coasts at 3,000 m/s in deep space with its engine off. What does it do, Pia?

    • It slows down steadily until it comes to a stop
    • It coasts, but its inertia wears out very slowly
    • It speeds up, since its inertia keeps adding speed
    • It keeps going at 3,000 m/s in a straight line

  10. Which one is not in equilibrium, Ren?

    • A car cruising at 25 m/s along a straight, level road
    • A ball at the top of its flight, momentarily at rest
    • A skydiver falling through the air at a steady 55 m/s
    • A heavy book resting on a flat desk in a classroom

  11. A box rests on a ramp. Tala says friction must be zero, since nothing moves. What is wrong with that?

    • Friction acts down the ramp and adds to gravity's pull on the box
    • Friction is zero for boxes that rest near the top of a ramp
    • Without friction, the weight's part down the ramp would make it slide
    • The normal force by itself balances the whole weight, so nothing is left over
PencilGopencilgo.com

11th grade Balanced forces, equilibrium and inertia worksheet – printable
Print: 123456

About this worksheet

Balanced forces, equilibrium and inertia. Every version has 10 questions, and the answer key prints on the second page.

What your child will learn

  • I can say that equilibrium means zero net force, at rest or at constant velocity. I can tell when an object is not in equilibrium, such as a ball at the top of its flight.
  • I can find the force that balances others along a line or at right angles.
  • I can balance a block on a ramp: friction = mg sin θ and normal force = mg cos θ.
  • I can explain inertia as a property of mass, not a force and not a matter of speed. I can predict what objects do when their support stops or vanishes: a block on a stopping cart, a coin on a flicked card, a satellite without gravity.

Standard: supports HS-PS2-1

Words to know

equilibrium: Zero net force: at rest or moving steadily in a straight line

inertia: How hard an object is to speed up, slow or turn; set by mass

balanced forces: Forces whose arrows add to zero

ramp angle θ: The tilt of a ramp above level

constant velocity: Same speed in the same direction

Common mistakes

Your child set the normal force equal to the weight. The surface pushes back just enough to balance every force along that line, so a push, a pull or a tilt changes it.

Your child subtracted a downward press from the weight. A press pushes down just as weight does, so both are balanced by the surface.

Your child used cosine where sine belongs. With the angle measured from the horizontal, the cable's upward part is T sin θ.

Questions parents ask

What is the most common mistake with balanced forces, equilibrium and inertia?

Your child set the normal force equal to the weight. The surface pushes back just enough to balance every force along that line, so a push, a pull or a tilt changes it.

Are these 11th grade science worksheets free to print?

Yes. All 6 printable versions at each level are free to print, with the answer key, and no account is needed.

More physics

See all Physics

Every sheet you scan goes into your child’s record: dated, marked and ready for the year-end portfolio. Homeschool records

Ready for easier practice?

Print a sheet, scan it when it’s done, and PencilGo picks the next one.

Create a free account