Introduction to Forces

Which units are used to measure force?

• newtons

• feet

• miles

• grams

Jill is pushing a box across the floor. Which represents the upward force perpendicular to the floor

• Fp

• Ff

• FN

• Fg

Which best describes two counteracting forces on an object

• using a dolly to push a box to another location

• two children pulling apart a wishbone

• a group of dogs pulling a dogsled across ice

• two people pushing a broken-down car up the road

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NGSS.MS-PS2-1

Which force best represents Fg

• a weight lifter is pushing a barbell upward with a force of 90N

• the weight of a barbell acting on a weight lifter is 80N

• the amount of upward force of a table on a box is 25N

• a box on a rough table has difficulty sliding past 25N or force

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NGSS.MS-PS2-4

Emmet is lifting a box vertically. Which forces are necessary for calculating the total force?

• Fp, Ff, and Fg

• Fp, and FN

• Fp, Fg, and Ff

• Fp and Fg

Which is the best example of forces acting in the same direction

• a boy lifting his chest off the ground during a pushup

• two football players pushing a tackling shed

• a person pulling out a garden hose from its reel

• two dogs playing tug-of-war with a rope

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NGSS.3-PS2-1

Haley is trying to pull an object upward. The below forces are acting on the object.

Fp= 5500 N

Fg- 6000 N

Which represents the net force?

• ← 500 N

• → 500 N

• ↑ 500 N

• ↓ 500 N

Tags

NGSS.MS-PS2-2

Polly is pushing a box across the floor with a force of 30 N. The force of gravity is -8 N, and the normal force is 8 N. Which value could describe the force of friction if Polly could not move the box?

• -30 N

• -8 N

• 8 N

• 30 N

Tags

NGSS.MS-PS2-2

An object is moving across a surface, but it does not gain or lose speed. Which best describes the object's force?

• the net force is positive

• the net force is zero

• the positive force is greater than the negative force

• the negative force is greater than the positive force

Tags

NGSS.MS-PS2-2

Which best explains parallel forces

• left and right forces that can be added together

• right and upward forces that cancel each other out

• addition of parallel forces that cannot result in a negative force

• left and downward forces that cancel each other out