(a) For the work-energy theorem, the work done to lift the can of paint is equal to the gravitational potential energy gained by it, therefore it is equal to
where m=3.4 kg is the mass of the can, g=9.81 m/s^2 is the gravitational acceleration and 
is the variation of height. Substituting the numbers into the formula, we find
(b) In this case, the work done is zero. In fact, we know from its definition that the work done on an object is equal to the product between the force applied F and the displacement:
However, in this case there is no displacement, so d=0 and W=0, therefore the work done to hold the can stationary is zero.
(c) In this case, the work done is negative, because the work to lower the can back to the ground is done by the force of gravity, which pushes downward. Its value is given by the same formula used in part (a):
D. it is thickest in the middle
Answer:
B and C
Explanation:
Because EMWs are varying magnetic and electric radiation traveling at 90° to each other propagating energy form one place to another through vibration of these magnetic and electric fields
Answer:
d. the actual motion is regular, but the speeds of particles are too large to observe the regular motion
Explanation:
The speeds of the particles are very large and comparatively the average free path is very small . Therefore time taken in covering the free path ( path between two consecutive collision with medium particles ) is very small . Hence the st line path covered by particles between two collision is less likely to be visible. Hence motion appears irregular or zig-zag.
An example of something that is not a proton would be an electron. It has a negative charge and has a charge of 1.6X10^-19 Coulombs.
