Answer:

Explanation:
We are given that
Potential difference=V=154 V
Surface charge density=
Using 
We know that


Where

Using the formula


Using 
Hence, the spacing between the plates=
Answer:
Answered
Explanation:
The girl whirling the ball should let go off ball when the ball is at a position such that tangent to the circle is in the direction of the target.
the tangent at any point in a circular path indicates the direction of velocity at that point. And the moment when the centripetal force is removed the ball will follow the tangential path at that moment.
A thermometer should be air dried so as to not damage it or anything similar. The three steps to cleaning it are washing, rinsing, and air drying it after. You shouldn't try to dry it other ways because it can damage it and this can cause a lot of troubles, so things cold air blowers or similar things can be very good in cleaning your thermometer.
Answer:
12.5 km
Explanation:
Since 30.0 minutes is half of an hour and the average speed is 25.0 km/h we can multiply the time by the speed to find the distance travelled.
25.0km/h x 0.5 hours = 12.5 km