| A | B |
|---|
| A 60.0-kg person climbs a flight of stairs 5.5 m high. How much work is required? | ??? |
| A 900-N crate rests on the floor. How much work is required to move it at constant speed (a) 6.0 m along the floor against a friction force of 180 N, and (b) 6.0 m vertically? | ??? |
| How much work did the movers do (horizontally) pushing a 150-kg crate 12.3 m across a rough floor without acceleration, if the effective coefficient of friction was 0.70? | ??? |
| How high will a 0.325-kg rock go if thrown straight up by someone who does 115 J of work on it? Neglect air resistance. | ??? |
| A hammerhead with a mass of 2.0 kg is allowed to fall onto a nail from a height of 0.40 m. What is the maximum amount of work it could do on the nail? Why do people not just "let it fall" but add their own force to the hammer as it falls? | ??? |
| What is the minimum work needed to push an 850-kg car 50 m up a 12 degree incline? (a) Ignore friction. (b) Assume the effective coefficient of friction is 0.25. | ??? |
| How long will it take a 1750-W motor to lift a 285-kg piano to a sixth-story window 16.0 m above? | ??? |
| What is the horsepower rating of a 150-W lightbulb? | ??? |
| How much work can a 3.0-hp motor do in 1.0 h? | ??? |
| A shot-putter accelerates a 7.3-kg shot from rest to 14 m/s. If this motion takes 2.0 s, what average power was developed? | ??? |
| A pump is to lift 8.00 kg of water per minute through a height of 3.50 m. What output rating (watts) should the pump motor have? | ??? |
