7. A force of 11 N is applied to the handle of a screwdriver being used to pry off the lid of a paint can. As the input force moves through a distance 0.3 m, the screwdriver does 3 J of work on the lid.

What is the efficiency of the screwdriver?

27%

91%

9.1%

11%

Using a wheel and axle, a farmer is trying to lift a bucket of water from the bottom of a well. the larger wheel has a radius of 40 cm compared to the axle that has a radius of 10 cm. if a bucket of water is 50 n, then how much effort is required to raise it? 12.5 n 200 n 2 n 500 n

Explain earth's motion, using the terms "precession" and "rotation" in your answer.

Why is it important always to use horizontal bars in unit fractions when performing unit conversions?