Work - Concepts and Problems

Work can be defined as a _____ acting over some amount of _____ to cause a change in _____.

• force, distance, energy

• force, time, energy

• force, time, distance

• force, distance, time

Tags

NGSS.HS-PS2-1

What is the common formula for work?

• W=F v cos (angle between the direction of motion and the force)

• W=F d cos (angle between the direction of motion and the force)

• W=F m cos (angle between the direction of motion and the force)

• W=F t cos (angle between the direction of motion and the force)

The unit for work is the _____.

• Newton

• kilogram

• Joule

• meter

When is work positive?

• Work is positive if a force is opposite the direction of motion.

• Work is positive if a force is in the same direction as the direction of motion.

• Work is positve if a force is perpendicular to the direction of motion.

When is work negative?

• Work is negative when a force is in the same direction as the direction of motion.

• Work is negative when a force is opposite the direction of motion.

• Work is negative when a force is perpendicular to the direction of motion.

Work is a _____.

• vector; the direction of the work vector

• vector; whether the work adds or removes energy from the object

• scalar; the direction of the work vector

• scalar; whether the work adds or removes energy from the object

A child moving at constant velocity carries a 2N ice-cream cone 1 m across a level surface.  What is the work done on the ice cream cone?

• 0 J
• 0.5 J
• 2 J
• 20 J

A construction worker pushes a wheelbarrow 5 m with a horizontal force of 50 N.  How much work is done?

• 10J
• 55J
• 250J
• 1250J

Tags

NGSS.HS-PS3-1

A child pulls a balloon for 12 m with a force of 1N at an angle of 60 degrees.  How much work does the child do on the balloon?

• -10J
• -6J
• 6J
• 12J

Tags

NGSS.MS-PS3-4

NGSS.MS-PS3-5

What is the total work done on the object? It moves 1 meter to the right.

• 0 Joules

• 0.5 Joules

• 500 Joules

• 50 Joules

Tags

NGSS.HS-PS3-1