Answer:
The radius of the curve that Car 2 travels on is 380 meters.
Explanation:
Speed of car 1, 
Radius of the circular arc, 
Car 2 has twice the speed of Car 1, 
We need to find the radius of the curve that Car 2 travels on have to be in order for both cars to have the same centripetal acceleration. We know that the centripetal acceleration is given by :

According to given condition,


On solving we get :

So, the radius of the curve that Car 2 travels on is 380 meters. Hence, this is the required solution.
Under general relativity, there is no 'before the Big Bang'. The problem is that time is itself a part of the universe and is affected by matter and energy. Because of the huge densities just after the Big Bang, time itself is warped in such a way that it cannot go back before that event. It is somewhat like asking what is north of the north pole.
The conservation of matter and energy states that the total amount of mass and energy at one time is the same at any other time. Notice how time is a crucial part of this statement. To even talk about conservation laws, you have to have time.
The upshot is that the Big Bang did not break the conservation laws because time itself is part of the universe and started at the Big Bang and because the conservation laws need to have time in their statements.
The length of a vector arrow represents an magnitude
Velocity = displacement (distance)/time
v=80m/4s
v=20m/s
velocity = 20 meters per second
Answer:
D) Grounding
Explanation:
The potential difference between cloud and ground leads to ionization of the atmosphere and resulting conduction through the air often to ground (although it can be between clouds at different potentials. I would say grounding, like the spark when you touch a hot battery terminal to ground on a car.