Suppose you lift a 20 kg box by a height of 1.0 m.

2 answers:

8 0

Answer: The work done in lifting something is W=mgh where m is the mass of the objet, g is the gravity acceleration and h is the height, this work is done because you are "fighting" against the force of gravity.

so in this case we have W = 20kg*9.8m/s*1m= 196N

9966 [12]2 years ago

6 0

W=mgh W=(20)(9.8)(1) w=196J

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The maximum gauge pressure in a hydraulic lift is 18.0 atm what is the largest size vehicle

victus00 [196]

There is a missing part in the question. Found the complete text on internet:
"What is the largest size vehicle (kg) it can lift if the diameter of the output line is 28.0 cm? "

Solution
The diameter of the piston is 28.0 cm, this means its radius is 14.0 cm (half the diameter), so the area of the piston is
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Therefore the maximum force the piston can lift is
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True [87]

Answer:

At the highest point the velocity is zero, the acceleration is directed downward.

Explanation:

This is a free-fall problem, in the case of something being thrown or dropped, the acceleration is equal to -gravity, so -9.80m/s^2. So, the acceleration is never 0 here.

I attached an image from my lecture today, I find it to be helpful. You can see that because of gravity the acceleration is pulled downwards.

At the highest point the velocity is 0, but it's changing direction and that's why there's still an acceleration there.

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