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.
Answer:
speed of each marble after collision will be 1.728 m/sec
Explanation:
We have given mass of the marble 
Velocity of marble 
Its collides with other marble of mass 25 gram
So mass of other marble 
Second marble is at so 
We have to find the velocity of second marble
From momentum conservation we know that
, here v is common velocity of both marble after collision
So 
v = 1.428 m /sec
So speed of each marble after collision will be 1.728 m/sec
Antioxidant are compounds found in foods..they help to prevent damage of the cell
Answer: The potential difference between the plates = 0.4061V
Explanation:
Given that the
Electric field strength E = 155 N/C
Distance d = 0.00262 m
From the definition of electric field strength, is the ratio of potential difference V to the distance between the plates. That is
E = V/d
Substitute E and d into the above formula
155 = V/0.00262
Cross multiply
V = 155 × 0.00262
V = 0.4061 V
The potential difference between the plates is 0.4061 V
It confirmed medeleeve's hypothesis (prediction) and showed the use of his table