Answer:
The average induced emf around the border of the circular region is 
.
Explanation:
Given that,
Radius of circular region, r = 1.5 mm
Initial magnetic field, B = 0
Final magnetic field, B' = 1.5 T
The magnetic field is pointing upward when viewed from above, perpendicular to the circular plane in a time of 125 ms. We need to find the average induced emf around the border of the circular region. It is given by the rate of change of magnetic flux as :
So, the average induced emf around the border of the circular region is .
The Luminosity of a star is proportional to its Effective Temperature to the 4th power and its Radius squared.
During the diving when a diver jumps off from platform he brings her knees and arms closer to the body
This is because when diver is in air he don't have any torque about his center of mass which shows that angular momentum of his body will remain constant during his motion in air
Now we can say product of his moment of inertia and his angular speed will remain constant always
So here if we decrease the moment of inertia of the body during our motion then angular speed will increase so that product will remain constant
and this is what the diver use during his diving
so correct answer will be
<u><em>It decreases her moment of inertia.</em></u>
Answer:
Yes, if the two carts are moving into opposite directions
Explanation:
The total momentum of the system of two carts is given by:
where
m1, m2 are the masses of the two carts
v1, v2 are the velocities of the two carts
Let's remind that v (the velocity) is a vector, so its sign depends on the direction in which the cart is moving.
We want to know if it is possible that the total momentum of the system can be zero, so it must be:
From this equation, we see that this condition can only occur if v1 and v2 have opposite signs. Opposite signs mean opposite directions: therefore, the total momentum can be zero if the two carts are moving into opposite directions.
In a direct current the electric charge flows in one direction.
in an alternating the electric charge changes in its direction periodically.
