Answer:
310.5 J
Explanation:
The total work done by Martha is equal to the increase in gravitational potential energy of the package, which is equal to
where
(mg) = 45 N is the weight of the package
is the increase in height of the package
The package is carried up 3 flights of stairs, each one with a height of 2.3 m, so the total increase in heigth is
And so, the work done by Martha is
Answer:
Explanation:
The weight of an object on Earth is given by , so we can calculate its mass by doing
, which for our values is:
<em>Nothing is being asked</em> about Io but if one wanted to know the weight <em>W'</em> of the watermelon there one just have to do:
In a series circuit the total current is the same throughout resistors and so:
The voltage is distributed throughout the resistors and so:
and the total resistance can be calculated by adding up the resistors resistance:
First thing is to calculate the total resistance and so:
And by Omh's law V=IR we have:
And so the total current of the circuit is 1.2 amps i.e. 1.2 A.