Understanding Work: Positive, Negative, and Zero

The video tutorial explains three types of work: positive, negative, and zero work. Positive work occurs when force and displacement are in the same direction, resulting in a positive value. Negative work happens when force and displacement are in opposite directions, leading to a negative value. Zero work is when force and displacement are perpendicular, or when there is no force or displacement. Examples are provided for each type to illustrate the concepts.

What are the three types of work discussed in the video?

• Positive, Negative, and Zero

• Kinetic, Potential, and Thermal

• Mechanical, Electrical, and Chemical

• Static, Dynamic, and Rotational

When is work considered positive?

• When there is no displacement

• When force and displacement are in the same direction

• When force and displacement are in opposite directions

• When force is perpendicular to displacement

In the example of a man pushing a trolley, why is the work done positive?

• Because the trolley is stationary

• Because the force is greater than the displacement

• Because both force and displacement are in the forward direction

• Because the force is applied at an angle

What is the angle between force and displacement in positive work?

• 45 degrees

• 90 degrees

• 0 degrees

• 180 degrees

What characterizes negative work?

• Force and displacement are in the same direction

• Force and displacement are perpendicular

• Force and displacement are in opposite directions

• There is no force applied

In the context of frictional force, why is the work done negative?

• Because there is no displacement

• Because frictional force is in the opposite direction to displacement

• Because frictional force is in the same direction as displacement

• Because frictional force is greater than the applied force

What is the angle between force and displacement in negative work?

• 0 degrees

• 45 degrees

• 90 degrees

• 180 degrees

When is work considered zero?

• When there is no force or displacement

• When force and displacement are in opposite directions

• When force and displacement are perpendicular

• When force and displacement are in the same direction

In the example of carrying luggage, why is the work done by gravitational force zero?

• Because gravitational force is in the same direction as displacement

• Because the luggage is not moving

• Because gravitational force is perpendicular to displacement

• Because there is no gravitational force

What is another condition that results in zero work?

• When force and displacement are in opposite directions

• When force and displacement are in the same direction

• When force is greater than displacement

• When there is no force acting on the body