Answer:
9.8 Joules (rounded to 2 significant figures)
Explanation:
Work done (J)= Force(N) x distance changed (m)
- Force= 9.80665 x 0.5kg
- Force= 4.90332 Newtons
- Distance changed= 5-3
- distance changed= 2m/s
--> work done= 4.90332 x 2
work done= 9.8 Joules
Answer:
C) No work is required to move the negative charge from point A to point B.
Explanation:
An equipotential surface is defined as a surface connecting all the points at the same potential.
Therefore, when a charge moves along an equipotential surface, it moves between points at same potential.
The work done when moving a charge is given by

where
q is the charge
is the potential difference between the initial and final point of motion of the charge
However, the charge in this problem moves along an equipotential surface: this means that the potential does not change, so

And so, the work done is also zero.
That's THERMAL energy, often referred to as "heat".
Answer:
B. The maximum angle decreases
Explanation:
If θ be the maximum angle of a slope that allows a crate placed on it to remain at rest , following condition exists .
tanθ = μ , θ is called angle of repose . μ is coefficient of static friction .
So the tan of angle of repose θ is proportional to coefficient of static friction.
If coefficient of static friction is less than .7 , naturally angle of repose will also become less ,ie, it at lower angle of inclination , the object will start slipping .