Answer:
-6112.26 J
Explanation:
The initial kinetic energy,
is given by
} where m is the mass of a body and
is the initial velocity
The final kinetic energy,
is given by
where
is the final velocity
Change in kinetic energy,
is given by

Since the skater finally comes to rest, the final velocity is zero. Substituting 0 for
and 12.6 m/s for
and 77 Kg for m we obtain

From work energy theorem, work done by a force is equal to the change in kinetic energy hence for this case work done equals <u>-6112.26 J</u>
One, three and five are correct.
Although if the second statement is saying that stars use gravitational force to support nuclear fusion which in turn produces energy then that would be correct, but I don’t think so :)
Answer:
so here it will move in circle with radius 4.06 cm
Explanation:
As we know that proton is moving towards west while the magnetic field is vertically upwards
So here the force on the proton must be perpendicular to the velocity
So here we have

so here we have

since force is perpendicular to the velocity so here it must be centripetal force
here we have

so we have



so here it will move in circle with radius 4.06 cm
Answer:
10
Explanation: Earth takes 24 hours to complete one spin, and Mars takes 25 hours. The gas giants rotate really fast. Jupiter takes just 10 hours to complete one rotation. Saturn takes 11 hours, Uranus takes 17 hours, and Neptune takes 16 hours.