Work done

How can we measure the work done by a force?

• Work = Force × Displacement × cosθ

• Work = Force × Displacement × sinθ

• Work = Force × Velocity × cosθ

• Work = Mass × Acceleration × Time

When is the work done by a force considered positive?

• When the force and displacement are perpendicular to each other

• When the force and displacement are in the same direction

• When the force and displacement are in opposite directions

• When there is no displacement

Which of the following is an example of negative work?

• A person lifting a bag upward

• A car accelerating on a road

• A ball rolling on the ground and coming to a stop due to friction

• A cyclist pedaling in the direction of motion

When is the work done by a force zero?

• When force is applied but there is no displacement

• When force is applied perpendicular to the displacement

• Both a and b

• None of these

A waiter carrying a tray of food walks horizontally at a constant velocity. What is the work done by the gravitational force on the tray?

• Positive work

• Negative work

• Zero work

• Infinite work

Work done is measured in terms of

• Newton

• Kilogram

• Joule

• Pascal