Answer:

Explanation:
Since the object is under a circular motion, according to Newton's second law, when the object is at the top of the circle we have:

Where
is the centripetal force and is given by:

Replacing and solving for T:

Answer:
<em>W=700 Joule</em>
Explanation:
<u>Physics Work
</u>
Is the dot product of the force vector by the displacement vector

When both the force and the displacements are pointed in the same direction, the formula reduces to its scalar version

The weightlifter is applying a net force of 350 N to lift the weights a distance of 2 m, thus the net work done is

Answer: Nitrogen
Explanation: Nitrogen makes up 78% of the atmosphere, Oxygen makes up 21%, and Argon 0.9%.
Water vaper makes up between 1-4%, depending on the region.
Carbon Dioxide makes up only about 0.04%.
If 56.5kJ are needed to raise the temp by 90°C and if the heater is 60% efficient that means that:
60% X y = 56.5kJ
where y is the electrical energy in kJ that the heater will use.
y = 94.2kJ