A student’s calculation for the work done on an object is shown.

Question

W=F×Δd


W=(140 N)×(30 cm)


W=4,200 J


Which statement describes the error in the work?

(1 point)
Responses

The operation is incorrect.
The operation is incorrect.

The units for work are incorrect.
The units for work are incorrect.

The distance must be converted to meters.
The distance must be converted to meters.

The force must be converted to joules.
The force must be converted to joules.

Answer 1

The correct response is:

The distance must be converted to meters.

In the calculation, the distance of 30 cm should be converted to meters (30 cm = 0.30 m) before calculating work, since the standard unit for distance in the formula for work is meters. Therefore, the calculation of work would then be \( W = 140 , \text{N} \times 0.30 , \text{m} \), which would give \( W = 42 , \text{J} \), not 4,200 J.