Answer:
A. The athlete isn’t doing any work because he doesn’t move the weight.
Explanation:
We must remember the definition of work, which says that work is equal to the product of mass by the distance displaced. In this case, the athlete only does work when he lifts the weight from the ground to the point where he holds the weight suspended.
So when he's holding the weight, he doesn't do any work.
if you're shopping for a rack switch, the component on the switch that tells you it can be mounted to a rack is the:
<h3>What are rack ears?</h3>
Rack ears are L-shaped objects that can be used to hold a rack switch firmly to the support walls. Rack ears are often found at the front panel of the rack which is to be mounted.
When a person purchases a rack switch and finds the rack ears there, it is a signal that the item can be secured firmly to rails. Sometimes, the rack ears also appear as extensions.
Learn more about rack ears here:
brainly.com/question/13318148
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Answer: 
Explanation:
The angular diameter 
of a spherical object is given by the following formula:
Where:
is the actual diameter
is the distance to the spherical object
Hence:
This is the angular diameter
Answer:
Explanation:
Given that,
Mass of the heavier car m_1 = 1750 kg
Mass of the lighter car m_2 = 1350 kg
The speed of the lighter car just after collision can be represented as follows
b) the change in the combined kinetic energy of the two-car system during this collision
substitute the value in the equation above
Hence, the change in combine kinetic energy is -2534.78J
