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musickatia [10]

3 years ago

11

Lucas is carrying his rock collection into class. He carries 30 pounds of rare rocks 15 feet into Classroom 6. It takes him 3 mi

nutes to get them into the classroom. What is Lucas's speed and level of work? Be sure to show your work with equations as part of your answer!

2 answers:

Tomtit [17]3 years ago

6 0

Explanation:

It is given that,

Force, F = 30 pounds = 133.4 N

Distance, d = 15 feet = 4.572 m

Time taken, t = 3 minutes = 180 seconds

Lucas's speed is given by the ratio of total displacement divided by total time taken. It is given by :

$s=\dfrac{d}{t}$

$s=\dfrac{4.572\ m}{180\ s}$

s = 0.0254 m/s

So, her speed is 0.0254 m/s.

Work done, W = F . d

W = 133.4 N × 4.572 m

W = 609.90 J

or

W = 610 J

Hence, this is the required solution.

weqwewe [10]3 years ago

3 0

you would multiply 30 by 15. because its the weight times the distance.

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Answer:

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