A worker pushes a wheelbarrow with a force of 40 N over a level distance of 6.0 m. If a frictional force of 24 N acts on the wheelbarrow in a direction opposite to that of the worker, what net work is done on the wheelbarrow?
worker work=40*6=240j
frictionwork:24*6=144j
net work= difference.
To find the net work done on the wheelbarrow, we need to consider both the work done by the worker and the work done by the frictional force.
The work done by the worker can be calculated using the formula:
Work = Force x Distance x Cos(angle)
where,
Force = 40 N (force exerted by the worker)
Distance = 6.0 m (level distance covered)
Angle = 0 degrees (since the force and the displacement are in the same direction)
Using this formula, we can calculate the work done by the worker:
Work by worker = 40 N x 6.0 m x Cos(0°)
= 40 N x 6.0 m x 1
= 240 J
Now, let's calculate the work done by the frictional force. The work done by friction is given by:
Work by friction = Force x Distance x Cos(angle)
where,
Force = 24 N (frictional force acting opposite to the direction of motion)
Distance = 6.0 m (the same level distance covered)
Angle = 180 degrees (since the force and the displacement are in opposite directions)
Using this formula, we can calculate the work done by friction:
Work by friction = 24 N x 6.0 m x Cos(180°)
= 24 N x 6.0 m x (-1)
= -144 J
Since the frictional force is acting in the opposite direction, the work done by the frictional force is negative.
Now, to find the net work done on the wheelbarrow, we subtract the work done by friction from the work done by the worker:
Net Work = Work by worker - Work by friction
= 240 J - (-144 J)
= 240 J + 144 J
= 384 J
Therefore, the net work done on the wheelbarrow is 384 J.
To find the net work done on the wheelbarrow, we can use the formula:
Net Work = Force × Distance × cos(θ)
In this case, the force applied by the worker is 40 N, the distance traveled is 6.0 m, and the angle between the force and the direction of motion is 0 degrees (since the force and distance are both in the same direction). So we have:
Net Work = 40 N × 6.0 m × cos(0°)
The cosine of 0 degrees is 1, so we can simplify the equation to:
Net Work = 40 N × 6.0 m × 1
Net Work = 240 N·m
Therefore, the net work done on the wheelbarrow is 240 N·m.