![michaelmatonis](/avatars/41573.jpg)
michaelmatonis
04.10.2019 •
Physics
Astudent lifts a 50 pound (lb) ball 4 feet (ft) in 5 seconds (s). how many joules of work has the student completed?
Solved
Show answers
More tips
- O Other What is a Disk Emulsifier and How Does it Work?...
- H Health and Medicine How to Calm Your Nerves? Expert Tips That Actually Work...
- A Animals and plants 5 Tips for Taking Care of Yews to Keep Them Green and Beautiful...
- S Sport How to wrap boxing hand wraps? Everything you need to know!...
- F Food and Cooking 10 Reasons Why You Should Avoid Giving Re-Gifts: An Informative Guide...
- F Family and Home Tender Care for Your Parquet: Is it Possible to Clean Parquet?...
- S Style and Beauty How Are Eyelash Extensions Applied? All Your Questions Answered...
- F Food and Cooking 10 Tips for Proper Sushi Consumption...
- S Style and Beauty Learn how to tie a keffiyeh on your head like a pro...
- S Style and Beauty How to Braid Hair with a Plaiting Machine: Tips and Recommendations...
Answers on questions: Physics
- P Physics Which of the following would most often be measured in light years...
- P Physics Which of the following is NOT available for drinking A) groundwater B) lakes C) rivers with tributaries D) frozen ice caps...
- P Physics If an orange is sitting 4m up in a tree and has a mass of 135 kg, then how much potential energy does it have....
- P Physics Calculate ke the of a car which has a mass of 1000 kg and is moving at the rate of 20 m/s....
- P Physics Why is effective data collection important when attempting to make a decision...
- P Physics Sally walks 1km from her home to school. When she arrives she tells her science teacher “ my velocity to school this morning was 15 minutes “. What would her teacher...
- P Physics A 0 20-kg hockey puck initially traveling 5.0 m/s is pushed on ice by a hockey stick with a constant force of 7.0 N over a distance of 8.0 m. Friction is negligible....
- P Physics A uniform magnetic field passes through a horizontal circular wire loop at an angle 15.1∘ from the vertical. The magnitude of the magnetic field B changes in time...
- P Physics Se lanza verticalmente hacia arriba un proyectil y alcanza una altura máxima de 100 metros de altura. ¿Cuál fue la velocidad hacia arriba con la que fue lanzada?...
- P Physics I need help pronto this is for a test and I’ll be sending another photo shortly...
Ответ:
Work = (50 lb) x (1 kg / 2.20462 lb) x (9.81 newton/kg)
x (4 feet) x (1 meter / 3.28084 feet)
= (50 x 9.81 x 4) / (2.20462 x 3.28084) newton-meter
= 271.3 joules .
We don't need to know how long the lift took, unless we
want to know how much power he was able to deliver.
Power = (work) / (time)
= (271.3 joule) / (5 sec) = 54.3 watts .
The easy way:
Work = (weight) x (distance)
= (50 pounds) x (4 feet) = 200 foot-pounds
Look up (online) how many joules there are in 1 foot-pound.
There are 1.356 joules in 1 foot-pound.
So 200 foot-pounds = (200 x 1.356) = 271.2 joules.
That's the easy way.
Ответ:
reading, counting,conversing