Answer:

Explanation:
Given:
- mass of car,

- distance of skidding after the application of brakes,

- coefficient of kinetic friction,

<u>So, the energy dissipated during the skidding of car:</u>
<em>Frictional force:</em>

where N = normal reaction by ground on the car


<em>Now from the work-energy equivalence:</em>


is the dissipated energy.
Answer:
The answer is: c. It does not move
Explanation:
Because the gravitational force is characterized by being an internal force within the Earth-particle system, in this case, the object of mass M. And since in this system there is no external force in the system, it can be concluded that the center of mass of the system will not move.
Answer:
E=0
Explanation:
Electric field due to each thin sheet of charge=\sigma/2\varepsilon
let us say the right plate has positive charge density \varepsilonand left sheet has a negative charge density -\varepsilon .
In the region between the plates,the electric field due to each plate is in same direction,
E=\sigma/2\varepsilon-(-\sigma/2\varepsilon)
E=\sigma/\varepsilon
in the region outside the plates, the field due to the plates is in opposite directions
E=-\sigma/2\varepsilon-(-\sigma/2\varepsilon)
E=-\sigma/2\varepsilon+\sigma/2\varepsilon
E=0
It is definitely letter D. <span>A1 and B1 are like poles, but there is not enough information to tell whether they are north poles or south poles.
A1 and B1 is either both north poles or both south poles. Repulsion of both magnets says it all--like poles always repel while opposite poles always attract. Thus, the best conclusion to this would be choice D.</span>
Answer:
B. 1 m/s
Explanation:
Metric unit conversions:
0.3 km = 300m
5 minutes = 5*60 = 300 seconds
So if a seal can reach a depth of 300m in a time of 300 seconds, its diving speed is the distance divided by time duration
v = s/t = 300/300 = 1m/s
So B is the correct answer