You're driving the orange car on an urban street and you want to turn right at this intersection. Is it safe to go?

No - The green car is too close.

At a speed of 50 kilometers per hour, the green car is traveling at approximately 14 meters per second. The average car length is about 4 meters, so the green car could reach your position in about one second (which is roughly the length of four cars). Therefore, turning is not safe. Ideally, you should have at least four seconds to ensure safety.