Let's solve each question using the provided word bank:
Word Bank:
acceleration, equilibrium, machine, force, power, inertia, work, velocity
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1. A ____________ is a device that makes work easier to do.
✔ Answer: machine
- A *machine* is any device that helps us do work more efficiently by changing the magnitude or direction of a force.
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2. When all forces acting on an object balance each other, the object is said to be in a state of ____________.
✔ Answer: equilibrium
- When net force is zero (forces are balanced), the object is in *equilibrium*. It will either remain at rest or move at constant velocity.
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3. ____________ is done when force moves an object.
✔ Answer: work
- *Work* is defined as force applied over a distance: $ W = F \cdot d $. If there's no movement, no work is done.
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4. ____________ is the rate at which work is done.
✔ Answer: power
- *Power* measures how quickly work is performed: $ P = \frac{W}{t} $. It's measured in watts (W).
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5. An object resists a change in motion because of ____________.
✔ Answer: inertia
- *Inertia* is the tendency of an object to resist changes in its motion. This is described by Newton’s First Law.
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6. The ____________ of a moving object describes its speed and direction.
✔ Answer: velocity
- *Velocity* is a vector quantity that includes both speed and direction. Speed alone is scalar.
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7. Gravity is a ____________ that pulls objects toward the center of the earth.
✔ Answer: force
- Gravity is a *force* of attraction between masses. Earth’s gravity pulls objects downward.
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8. ____________ is the rate at which velocity changes.
✔ Answer: acceleration
- *Acceleration* is the change in velocity over time: $ a = \frac{\Delta v}{\Delta t} $. It can involve speeding up, slowing down, or changing direction.
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✔ Final Answers:
1.
machine
2.
equilibrium
3.
work
4.
power
5.
inertia
6.
velocity
7.
force
8.
acceleration
All words from the bank are used exactly once — perfect!
Parent Tip: Review the logic above to help your child master the concept of force and motion worksheet 8th grade.
